[llvm] [revert_checker] replace Phabricator URIs with GitHub URIs (PR #92102)

[George Burgess IV via llvm-commits]

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@@ -284,16 +284,11 @@ def _main() -> None:
                 all_reverts.append(revert)
 
     for revert in all_reverts:
-        sha_fmt = (
-            f"https://reviews.llvm.org/rG{revert.sha}"
-            if opts.review_url
-            else revert.sha
-        )
-        reverted_sha_fmt = (
-            f"https://reviews.llvm.org/rG{revert.reverted_sha}"
-            if opts.review_url
-            else revert.reverted_sha
+        sha_prefix = (
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gburgessiv wrote:

`sha_prefix` is loop invariant, so please move this assignment above the loop 

https://github.com/llvm/llvm-project/pull/92102