[Chapel Merge] Make `third-party/llvm/update-bundled.sh` less redundant

Branch: refs/heads/main
Revision: ca25b684f4ea65835d6f833f4f3f40d9586d4698
Author: arifthpe
Link: Make `third-party/llvm/update-bundled.sh` less redundant by arifthpe · Pull Request #28792 · chapel-lang/chapel · GitHub
Log Message:
Make third-party/llvm/update-bundled.sh less redundant (#28792)

Add set -x and cd $LLVM_DIR at the top of
third-party/llvm/update-bundled.sh rather than repeating those steps
on each line.

While here, also set the rest of set -exuo pipefail as a good
practice.

[reviewed by @jabraham17, thanks!]

Testing:

  • test run of script worked

Compare: Comparing bc7e44038db46f682a69b07b00688857f0beb773...19a4e3f71eebc96acb00070274363a614722ff1e · chapel-lang/chapel · GitHub

Diff:
M third-party/llvm/update-bundled.sh
https://github.com/chapel-lang/chapel/pull/28792.diff