Change 6.2.0rc1 to 6.2.0rc2 in version_switch.js (#5240)

Author: Meghan Jones

doc/rst/_static/version_switch.js

@@ -12,7 +12,7 @@
   var all_versions = {
     'latest': 'latest',
     'dev': 'dev',
-    '6.2.0rc1': '6.2.0rc1',
+    '6.2.0rc2': '6.2.0rc2',
     '6.1': '6.1',
     '6.0': '6.0',
     '5.4': '5.4',