[clang] [clang-format] Add option to remove leading blank lines (PR #91221)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-darwin` running on `doug-worker-3` while building `clang` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/23/builds/331

Here is the relevant piece of the build log for the reference:
```
Step 5 (build-unified-tree) failure: build (failure)
...
203.330 [1692/12/4091] Linking CXX static library lib/libclangTidyPlugin.a
203.359 [1691/12/4092] Linking CXX static library lib/libclangTidyMain.a
206.004 [1690/12/4093] Linking CXX executable bin/clang-tidy
208.168 [1689/12/4094] Linking CXX executable bin/clang-include-cleaner
208.217 [1688/12/4095] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/FileDistance.cpp.o
209.416 [1687/12/4096] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/CollectMacros.cpp.o
209.467 [1686/12/4097] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/FS.cpp.o
209.517 [1685/12/4098] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/FuzzyMatch.cpp.o
210.983 [1684/12/4099] Building CXX object tools/clang/tools/extra/include-cleaner/unittests/CMakeFiles/ClangIncludeCleanerTests.dir/LocateSymbolTest.cpp.o
213.402 [1683/12/4100] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/Format.cpp.o
FAILED: tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/Format.cpp.o 
CCACHE_CPP2=yes CCACHE_HASHDIR=yes /usr/local/bin/ccache /usr/bin/clang++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/Users/buildbot/buildbot-root/x86_64-darwin/build/tools/clang/tools/extra/clangd -I/Users/buildbot/buildbot-root/x86_64-darwin/llvm-project/clang-tools-extra/clangd -I/Users/buildbot/buildbot-root/x86_64-darwin/llvm-project/clang-tools-extra/clangd/../include-cleaner/include -I/Users/buildbot/buildbot-root/x86_64-darwin/build/tools/clang/tools/extra/clangd/../clang-tidy -I/Users/buildbot/buildbot-root/x86_64-darwin/llvm-project/clang/include -I/Users/buildbot/buildbot-root/x86_64-darwin/build/tools/clang/include -I/Users/buildbot/buildbot-root/x86_64-darwin/build/include -I/Users/buildbot/buildbot-root/x86_64-darwin/llvm-project/llvm/include -I/Users/buildbot/buildbot-root/x86_64-darwin/llvm-project/clang-tools-extra/pseudo/lib/../include -isystem /usr/local/include -fPIC -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -fno-common -Woverloaded-virtual -Wno-nested-anon-types -O3 -DNDEBUG -std=c++17 -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX14.4.sdk  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/Format.cpp.o -MF tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/Format.cpp.o.d -o tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/Format.cpp.o -c /Users/buildbot/buildbot-root/x86_64-darwin/llvm-project/clang-tools-extra/clangd/Format.cpp
/Users/buildbot/buildbot-root/x86_64-darwin/llvm-project/clang-tools-extra/clangd/Format.cpp:284:11: error: no member named 'KeepEmptyLinesAtTheStartOfBlocks' in 'clang::format::FormatStyle'
    Style.KeepEmptyLinesAtTheStartOfBlocks = true;
    ~~~~~ ^
1 error generated.
216.674 [1683/11/4101] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/FindSymbols.cpp.o
219.272 [1683/10/4102] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/Diagnostics.cpp.o
219.370 [1683/9/4103] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/ClangdServer.cpp.o
220.840 [1683/8/4104] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/CodeComplete.cpp.o
222.855 [1683/7/4105] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/GlobalCompilationDatabase.cpp.o
223.733 [1683/6/4106] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/ClangdLSPServer.cpp.o
223.795 [1683/5/4107] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/AST.cpp.o
224.448 [1683/4/4108] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/Headers.cpp.o
225.595 [1683/3/4109] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/DumpAST.cpp.o
226.600 [1683/2/4110] Building CXX object tools/clang/tools/extra/include-cleaner/unittests/CMakeFiles/ClangIncludeCleanerTests.dir/FindHeadersTest.cpp.o
228.749 [1683/1/4111] Building CXX object tools/clang/tools/extra/clangd/CMakeFiles/obj.clangDaemon.dir/FindTarget.cpp.o
ninja: build stopped: subcommand failed.

```

https://github.com/llvm/llvm-project/pull/91221