Fixing consent manager white screen issue

[anjuchamantha]

Fixing consent manager white screen issue

This PR fixes consent manager white screen issue and logout issue.

Issue:

• Whitescreen in consent manager portal. #134

When the consentmgr.war is built from the open source accelerator repo and deployed, and go to https://localhost:9446/consentmgr/ there is a white screen coming.

This is due to an attempt to get an id_token to a user which is not initialized. This PR fixes this.

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Development Checklist

1. Build complete solution with pull request in place.
2. Ran checkstyle plugin with pull request in place.
3. Ran Findbugs plugin with pull request in place.
4. Ran FindSecurityBugs plugin and verified report.
5. Formatted code according to WSO2 code style.
6. Have you verified the PR doesn't commit any keys, passwords, tokens, usernames, or other secrets?
7. Migration scripts written (if applicable).
8. Have you followed secure coding standards in WSO2 Secure Engineering Guidelines?