Add indexes to timestamp field in oauth_nonce

[KarlDeux]

Description

Inclusion of indexes into timestamp field in order to avoid deadlocks while on erasing old records.

Fixed Issues (if relevant)

1. Deadlock occurs using REST API & OAuth 1.0a under high concurrency  #10346: Deadlock occurs using REST API & OAuth 1.0a under high concurrency

Manual testing scenarios

1. Pull the code and run php bin/magento setup:upgrade
2. Create thousands of OAuth 1.0a requests to REST API (eg concurrency of 5 / sec)
3. Requests should complete successfully

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[dmanners]

Hi @KarlDeux we are looking to get a test case sorted for this. Would you be able to help us out. #10346 (comment)

[KarlDeux]

Hi @dmanners, just replied to the comment.
Sorry for the late response, It's been some crazily busy days.

[dmanners]

No worries @KarlDeux thanks for getting back to us on this.

[magento-engcom-team]

Hi @KarlDeux. Thank you for your contribution.
Changes from your Pull Request will be available with the upcoming 2.2.6 release.

Please, consider to port this solution to 2.3 release line.
You may use Porting tool to port commits automatically.