[libc++] Stop uploading crash diagnostics in the CI

This seems to break the CI right now, and I've never once used
those artifacts to debug something. In case of problems, we could
always just modify a failing PR to include the required crash
diagnostics in the artifacts as a one-off thing.

Author: ldionne

.github/workflows/libcxx-build-and-test.yaml

@@ -43,7 +43,6 @@ env:
   LLVM_OLDEST_VERSION: "17"
   GCC_STABLE_VERSION: "13"
   LLVM_SYMBOLIZER_PATH: "/usr/bin/llvm-symbolizer-19"
-  CLANG_CRASH_DIAGNOSTICS_DIR: "crash_diagnostics"
 
 jobs:
   stage1:
@@ -82,7 +81,6 @@ jobs:
             **/CMakeConfigureLog.yaml
             **/CMakeError.log
             **/CMakeOutput.log
-            **/crash_diagnostics/*
   stage2:
     if: github.repository_owner == 'llvm'
     runs-on: libcxx-self-hosted-linux
@@ -128,7 +126,6 @@ jobs:
             **/CMakeConfigureLog.yaml
             **/CMakeError.log
             **/CMakeOutput.log
-            **/crash_diagnostics/*
   stage3:
     if: github.repository_owner == 'llvm'
     needs: [ stage1, stage2 ]
@@ -192,7 +189,6 @@ jobs:
             **/CMakeConfigureLog.yaml
             **/CMakeError.log
             **/CMakeOutput.log
-            **/crash_diagnostics/*
 
   macos:
     needs: [ stage1 ]
@@ -235,7 +231,6 @@ jobs:
             **/CMakeConfigureLog.yaml
             **/CMakeError.log
             **/CMakeOutput.log
-            **/crash_diagnostics/*
 
   windows:
     runs-on: windows-2022