update versions file for rc3 release (#7096)

# Description

update versions file for rc3 release

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Fixes: #issue_number

Signed-off-by: vinayada1 <28875764+vinayada1@users.noreply.github.com>

versions.yaml

@@ -1,6 +1,6 @@
 supported:
   - channel: '0.30'
-    version: 'v0.30.0-rc2'
+    version: 'v0.30.0-rc3'
   - channel: '0.29'
     version: 'v0.29.0'
 deprecated: