Make unchangedTextChangeRange const (#55836)

src/compiler/utilitiesPublic.ts

@@ -403,7 +403,7 @@ export function createTextChangeRange(span: TextSpan, newLength: number): TextCh
     return { span, newLength };
 }
 
-export let unchangedTextChangeRange = createTextChangeRange(createTextSpan(0, 0), 0); // eslint-disable-line prefer-const
+export const unchangedTextChangeRange = createTextChangeRange(createTextSpan(0, 0), 0);
 
 /**
  * Called to merge all the changes that occurred across several versions of a script snapshot

tests/baselines/reference/api/typescript.d.ts

@@ -9153,7 +9153,7 @@ declare namespace ts {
     function isJSDocLinkLike(node: Node): node is JSDocLink | JSDocLinkCode | JSDocLinkPlain;
     function hasRestParameter(s: SignatureDeclaration | JSDocSignature): boolean;
     function isRestParameter(node: ParameterDeclaration | JSDocParameterTag): boolean;
-    let unchangedTextChangeRange: TextChangeRange;
+    const unchangedTextChangeRange: TextChangeRange;
     type ParameterPropertyDeclaration = ParameterDeclaration & {
         parent: ConstructorDeclaration;
         name: Identifier;