Test: Rename run_spec to runFormatTest (#15943)

eslint.config.js

@@ -320,7 +320,7 @@ export default [
   {
     files: ["tests/format/**/*.js"],
     rules: {
-      "prettier-internal-rules/no-legacy-format-test-fixtures": "error",
+      "prettier-internal-rules/no-legacy-format-test": "error",
     },
   },
   {
@@ -340,8 +340,8 @@ export default [
     },
     languageOptions: {
       globals: {
-        run_spec: "readonly",
         runCli: "readonly",
+        runFormatTest: "readonly",
       },
     },
   },