chore(rulesets): rename to oas3-server-variables

Author: P0lip

packages/rulesets/src/oas/__tests__/openapi-server-variables.test.ts renamed to packages/rulesets/src/oas/__tests__/oas3-server-variables.test.ts

@@ -1,7 +1,7 @@
 import { DiagnosticSeverity } from '@stoplight/types';
 import testRule from './__helpers__/tester';
 
-testRule('openapi-server-variables', [
+testRule('oas3-server-variables', [
   {
     name: 'valid case',
     document: {

packages/rulesets/src/oas/index.ts

@@ -692,7 +692,7 @@ const ruleset = {
         function: oasUnusedComponent,
       },
     },
-    'openapi-server-variables': {
+    'oas3-server-variables': {
       description: 'Server variables must be defined and valid and there must be no redundant variables.',
       message: '{{error}}',
       severity: 0,