Remove jsx as JavaScript React language ID

Fixes microsoft#4741

Author: gregvanl

Diff for: docs/languages/identifiers.md

@@ -82,7 +82,7 @@ HTML | `html`
 Ini | `ini`
 Java | `java`
 JavaScript | `javascript`
-JavaScript React | `javascriptreact`, `jsx`
+JavaScript React | `javascriptreact`
 JSON | `json`
 JSON with Comments | `jsonc`
 LaTeX | `latex`