fix diffErroredPatch erroring

Author: Nuckyz

src/webpack/patchWebpack.ts

@@ -650,9 +650,12 @@ function patchFactory(moduleId: PropertyKey, originalFactory: AnyModuleFactory):
 function diffErroredPatch(code: string, lastCode: string, match: RegExpMatchArray) {
     const changeSize = code.length - lastCode.length;
 
+    const matchIndex = match?.index ?? 0;
+    const matchLength = match?.[0]?.length ?? 0;
+
     // Use 200 surrounding characters of context
-    const start = Math.max(0, match.index! - 200);
-    const end = Math.min(lastCode.length, match.index! + match[0].length + 200);
+    const start = Math.max(0, matchIndex - 200);
+    const end = Math.min(lastCode.length, matchIndex + matchLength + 200);
     // (changeSize may be negative)
     const endPatched = end + changeSize;