Downgrade markdown version

[andreia-ferreira]

The latest markdown versions after 0.7.3 cause the following issue to be flagged on the Google Play Console:

This PR downgrades the version and adds ignore fields in the dependabot file so that it doesn't try to update to any of the recent releases where this issue is still present

@shobhitagarwal1612 PTAL?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 67.49%. Comparing base (4b17121) to head (0ce2907).

Additional details and impacted files

@@            Coverage Diff            @@
##             master    #3859   +/-   ##
=========================================
  Coverage     67.49%   67.49%           
  Complexity     1850     1850           
=========================================
  Files           410      410           
  Lines         10818    10818           
  Branches       1428     1428           
=========================================
  Hits           7302     7302           
  Misses         2768     2768           
  Partials        748      748           

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.