Sentry configuration

[lincmba]

IMPORTANT: Where possible all PRs must be linked to a Github issue

Resolves https://github.com/onaio/fhir-gateway-extension/issues/33

Engineer Checklist

• [ ] I have written Unit tests for any new feature(s) and edge cases for bug fixes
• [ ] I have run mvn spotless:check to check my code follows the project's style guide
• [ ] I have run mvn clean test jacoco:report to confirm the coverage report was generated at plugins/target/site/jacoco/index.html
• [ ] I ran mvn clean package right before creating this pull request.

[ndegwamartin]

Closing this in favor of https://github.com/onaio/fhir-gateway-extension/pull/44