[clang-tools-extra] [clang-doc] Wire Markdown parser into MDGenerator for fenced code blocks (PR #201746)

[via cfe-commits]

github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Linux-->
# :penguin: Linux x64 Test Results

* 3271 tests passed
* 7 tests skipped
* 1 test failed

## Failed Tests
(click on a test name to see its output)

### Extra Tools Unit Tests
<details>
<summary>Extra Tools Unit Tests.clang-doc/_/ClangDocTests/MDGeneratorTest/emitCommentMD</summary>

```
Script:
--
/home/gha/actions-runner/_work/llvm-project/llvm-project/build/tools/clang/tools/extra/unittests/clang-doc/./ClangDocTests --gtest_filter=MDGeneratorTest.emitCommentMD
--
/home/gha/actions-runner/_work/llvm-project/llvm-project/clang-tools-extra/unittests/clang-doc/MDGeneratorTest.cpp:424
Expected equality of these values:
  Expected
    Which is: "### f\n\n*void f(int I, int J)*\n\n*Defined at test.cpp#10*\n\n\n\n Brief description.\n\n Extended description that continues onto the next line.\n\n<ul \"class=test\">\n\n<li>\n\n Testing.</ul>\n\n\n\n The description continues.\n\n**I** [out] is a parameter.\n\n**J** is a parameter.\n\n**return** void\n\n"
  Actual.str()
    Which is: "### f\n\n*void f(int I, int J)*\n\n*Defined at test.cpp#10*\n\n\n\nBrief description.\n\nExtended description thatcontinues onto the next line.\n\n<ul \"class=test\">\n\n<li>\n\n Testing.</ul>\n\n\n\n The description continues.\n\n**I** [out] is a parameter.\n\n**J** is a parameter.\n\n**return** void\n\n"
With diff:
@@ -7,7 +7,7 @@
 
 
- Brief description.
+Brief description.
 
- Extended description that continues onto the next line.
+Extended description thatcontinues onto the next line.
 
 <ul \"class=test\">



```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/201746