chore(rendererTemplateRef): added dev warning for duplicated ref

Author: tsiotska

packages/runtime-core/src/rendererTemplateRef.ts

@@ -115,7 +115,15 @@ export function setRef(
           } else {
             if (!isArray(existing)) {
               if (_isString) {
-                if (oldRef !== ref) {
+                if (oldRef === ref) {
+                  if (__DEV__) {
+                    warn(
+                      'Duplicate template ref detected:',
+                      ref,
+                      `(${typeof ref}). Ref names must be unique within the same scope.`,
+                    )
+                  }
+                } else {
                   refs[ref] = [refValue]
                   if (canSetSetupRef(ref)) {
                     setupState[ref] = refs[ref]
@@ -130,7 +138,15 @@ export function setRef(
             }
           }
         } else if (_isString) {
-          if (oldRef !== ref) {
+          if (oldRef === ref) {
+            if (__DEV__) {
+              warn(
+                'Duplicate template ref detected:',
+                ref,
+                `(${typeof ref}). Ref names must be unique within the same scope.`,
+              )
+            }
+          } else {
             refs[ref] = value
             if (canSetSetupRef(ref)) {
               setupState[ref] = value