[clang] Revert "Reapply "[Clang][Sema] Refactor collection of multi-level template argument lists (#106585, #111173)" (#111852)" (PR #115159)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-sie-win` running on `sie-win-worker` while building `clang` at step 7 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/46/builds/7441

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang :: CXX/temp/temp.decls/temp.spec.partial/temp.spec.partial.member/p2.cpp' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
z:\b\llvm-clang-x86_64-sie-win\build\bin\clang.exe -cc1 -internal-isystem Z:\b\llvm-clang-x86_64-sie-win\build\lib\clang\20\include -nostdsysteminc -std=c++20 -fsyntax-only -verify Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CXX\temp\temp.decls\temp.spec.partial\temp.spec.partial.member\p2.cpp
# executed command: 'z:\b\llvm-clang-x86_64-sie-win\build\bin\clang.exe' -cc1 -internal-isystem 'Z:\b\llvm-clang-x86_64-sie-win\build\lib\clang\20\include' -nostdsysteminc -std=c++20 -fsyntax-only -verify 'Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CXX\temp\temp.decls\temp.spec.partial\temp.spec.partial.member\p2.cpp'
# .---command stderr------------
# | error: 'expected-error' diagnostics seen but not expected: 
# |   File Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CXX\temp\temp.decls\temp.spec.partial\temp.spec.partial.member\p2.cpp Line 73: static assertion failed due to requirement 'A<int>::B<int &>::y == 4'
# |   File Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CXX\temp\temp.decls\temp.spec.partial\temp.spec.partial.member\p2.cpp Line 77: static assertion failed due to requirement 'A<int>::x<int &> == 4'
# | error: 'expected-note' diagnostics seen but not expected: 
# |   File Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CXX\temp\temp.decls\temp.spec.partial\temp.spec.partial.member\p2.cpp Line 73: expression evaluates to '3 == 4'
# |   File Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CXX\temp\temp.decls\temp.spec.partial\temp.spec.partial.member\p2.cpp Line 77: expression evaluates to '3 == 4'
# | 4 errors generated.
# `-----------------------------
# error: command failed with exit status: 1

--

********************


```

</details>

https://github.com/llvm/llvm-project/pull/115159