Fix cache expiration-related issues in Auto Polling mode

[adams85]

Describe the purpose of your pull request

This PR fixes multiple issues in Auto Polling mode:

• Cache expiration should be checked in every poll iteration, not just in the first one to reduce network traffic when the SDK uses a shared cache.
• Cache synchronization should happen even in offline mode in every poll iteration, not just in the first one to update in-memory cache when the SDK uses a shared cache.

Related issues (only if applicable)

https://trello.com/c/gnqqRydc

Requirement checklist (only if applicable)

• [x] I have covered the applied changes with automated tests.
• [x] I have executed the full automated test set against my changes.
• [x] I have validated my changes against all supported platform versions.
• [x] I have read and accepted the contribution agreement.

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud