feat(ls): finalize support for OpenAPI 3.0.x Spec Ext lint rules

Refs #2033

Author: char0n

packages/apidom-ls/src/config/openapi/discriminator/lint/allowed-fields-3-0.ts

@@ -10,6 +10,12 @@ const allowedFields3_0Lint: LinterMeta = {
   linterFunction: 'allowedFields',
   linterParams: [['propertyName', 'mapping']],
   marker: 'key',
+  targetSpecs: [
+    { namespace: 'openapi', version: '3.0.0' },
+    { namespace: 'openapi', version: '3.0.1' },
+    { namespace: 'openapi', version: '3.0.2' },
+    { namespace: 'openapi', version: '3.0.3' },
+  ],
 };
 
 export default allowedFields3_0Lint;

packages/apidom-ls/src/config/openapi/paths/lint/keys--pattern.ts

@@ -4,10 +4,10 @@ import { LinterMeta } from '../../../../apidom-language-types';
 const keysPatternLint: LinterMeta = {
   code: ApilintCodes.OPENAPI3_0_PATHS_KEYS_PATTERN,
   source: 'apilint',
-  message: 'Paths Object keys must match the regular expression: `^/`',
+  message: 'Paths Object keys must match the regular expression: `^(/|x-)`',
   severity: 1,
   linterFunction: 'apilintKeysRegex',
-  linterParams: ['^/'],
+  linterParams: ['^(/|x-)'],
   marker: 'key',
   data: {},
 };