clang: Upgrade to 18.1.7

[kraj]

• 768118d1ad38 [clang-format] Fix a bug in formatting goto labels in macros (#92494)
• 8c0fe0d65ed8 release/18.x: [clang-format] Don't always break before << between str… (#94091)
• 7e6ece9b4f2d [PPCMergeStringPool] Only replace constant once (#92996)
• 1ce2d26cd2e9 Bump version to 18.1.7 (#93723)

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