Add codecov for kibana reports & Add README badges

[zhongnansu]

Issue #, if available:

Description of changes:

• Add codecov for Kibana-reports
• Add readme badges

TODO:

• Add test coverage for reports-scheduler plugin once we add unit test
• Add badges link to ODFE forum once we have the reporting category

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (dev@269ffbe). Click here to learn what that means.
The diff coverage is n/a.

@@          Coverage Diff           @@
##             dev     #248   +/-   ##
======================================
  Coverage       ?   74.75%           
======================================
  Files          ?       32           
  Lines          ?     1739           
  Branches       ?      340           
======================================
  Hits           ?     1300           
  Misses         ?      434           
  Partials       ?        5           

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