Update and rename aria-aria-tabindex.md to aria-tabindex.md

rename file name and update title in file

Author: Rabia2219

…ity-patterns-index/aria-aria-tabindex.md …sibility-patterns-index/aria-tabindex.mddocs/getting-started/accessibility-patterns-index/aria-aria-tabindex.md renamed to docs/getting-started/accessibility-patterns-index/aria-tabindex.md docs/getting-started/accessibility-patterns-index/aria-aria-tabindex.md renamed to docs/getting-started/accessibility-patterns-index/aria-tabindex.md

@@ -1,4 +1,4 @@
-# ARIA - ARIA tabindex
+# ARIA tabindex
 - WAVE Category: ARIA
 - WAVE ARIA: ARIA tabindex