[llvm] [Support][YamlTraits] Add quoting for keys in textual YAML representation (PR #88763)

[Matt Arsenault via llvm-commits]

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@@ -3,7 +3,7 @@
 ; RUN: FileCheck --check-prefix=SUMMARY %s < %t
 
 ; SUMMARY:     GlobalValueMap:
-; SUMMARY-NEXT:  42:
+; SUMMARY-NEXT:  '42':
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arsenm wrote:

Should quotes only be emitted in the necessary cases?

https://github.com/llvm/llvm-project/pull/88763