[clang-tools-extra] [clang-tidy][NFC] Remove regex hacks to match full lines in tests (PR #162293)

[Nicolas van Kempen via cfe-commits]

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@@ -42,31 +42,31 @@ void S::operator_equals() {
   m_b1 = (i > 2);
   if (m_b1 == true) {
     // CHECK-MESSAGES: :[[@LINE-1]]:15: warning: {{.*}} to boolean operator
-    // CHECK-FIXES: {{^  if \(m_b1\) {$}}
+    // CHECK-FIXES: if (m_b1)
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nicovank wrote:

Many `if` statements in this file have a trailing `{` (this file has `--match-partial-fixes` which is why this still works).

https://github.com/llvm/llvm-project/pull/162293