fix: environment options parsing error

Previously vitest failed to parse environment options when they were
provided as a single line doc block like so:

    /** @vitest-environment-options {"url": "https://vitejs.dev"} */

The regular expression erroneously captured the JSON as well as " */".

packages/vitest/src/utils/test-helpers.ts

@@ -58,7 +58,7 @@ export async function groupFilesByEnv(
       )
 
       const envOptions = JSON.parse(
-        code.match(/@(?:vitest|jest)-environment-options\s+?(.+)/)?.[1]
+        code.match(/@(?:vitest|jest)-environment-options\s+?(.+?)(?=\s*\*\/)/)?.[1]
         || 'null',
       )
       const envKey = env === 'happy-dom' ? 'happyDOM' : env