Auto merge of #15005 - aneeshusa:fix-git-author-setting-for-brew-upload, r=jdm

Fix git author setting for brew upload

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The fix from #14935 wasn't quite right.

cc @paulrouget

---
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- [ ] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix servo/saltfs#575 properly (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because they should be tested by running the mac-nightly builder

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etc/ci/upload_nightly.sh

@@ -11,7 +11,9 @@ shopt -s failglob
 
 
 usage() {
-    printf "usage: ${0} android|linux|mac|macbrew|windows-gnu|windows-msvc\n"
+    printf \
+        "usage: %s android|linux|mac|macbrew|windows-gnu|windows-msvc\n" \
+        "${0}"
 }
 
 
@@ -52,8 +54,10 @@ update_brew() {
        > "${tmp_dir}/Formula/servo-bin.rb"
 
   git -C "${tmp_dir}" add ./Formula/servo-bin.rb
-  git -C "${tmp_dir}" commit \
-      --author="Tom Servo <servo@servo.org>" \
+  git -C "${tmp_dir}" \
+      -c user.name="Tom Servo" \
+      -c user.email="servo@servo.org" \
+      commit \
       --message="Version bump: ${version}"
 
   git -C "${tmp_dir}" push -qf \