[llvm] release-binaries: Parallelize steps to reduce total run time (PR #218201)

[via llvm-commits]

================
@@ -337,8 +354,27 @@
       run: |
         xz -dc "$RELEASE_BINARY_FILENAME" | "$ZSTD" --ultra -22 -T0 -o "$RELEASE_BINARY_FILENAME_ZSTD"
 
+    - name: Install LLDB test Python dependencies
+      id: lldb-deps
+      if: runner.os == 'Linux'
+      run: |
+        python -m pip install -r lldb/test/requirements.txt
+
+    - name: Run Tests
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github-advanced-security[bot] wrote:

## CodeQL / Cache Poisoning via execution of untrusted code

Potential cache poisoning in the context of the default branch due to privilege checkout of untrusted code from [needs.prepare.outputs.ref](1). ([schedule](2)).
Potential cache poisoning in the context of the default branch due to privilege checkout of untrusted code from [needs.prepare.outputs.ref](1). ([workflow_dispatch](3)).
Potential cache poisoning in the context of the default branch due to privilege checkout of untrusted code from [needs.prepare.outputs.ref](1). ([workflow_dispatch](4)).

[Show more details](https://github.com/llvm/llvm-project/security/code-scanning/2317)

https://github.com/llvm/llvm-project/pull/218201