Fix: Refetch reference after raising file reference expired exception

[Lqlsoftware]

This fix works for handling the FILE_REFERENCE_EXPIRED exception.
The script will try 3 times to refetch the reference which is expired before XD.

[codecov]

Codecov Report

Merging #62 (5933bbb) into master (d8fd03d) will decrease coverage by 4.07%.
The diff coverage is 61.53%.

@@            Coverage Diff             @@
##           master      #62      +/-   ##
==========================================
- Coverage   95.14%   91.07%   -4.08%     
==========================================
  Files           2        2              
  Lines         103      112       +9     
==========================================
+ Hits           98      102       +4     
- Misses          5       10       +5     

Impacted Files	Coverage Δ
media_downloader.py	88.63% <61.53%> (-5.04%)	⬇️

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[Dineshkarthik]

@Lqlsoftware are you working on fixing the code coverage?
If not I can pull in your changes and write required unit-tests and create a new PR which supersedes this one.

[Lqlsoftware]

@Dineshkarthik Sorry, I was doing something else today.
The low code coverage is caused by except of 400-request exception, client.get_messages(), log. warning() and log.error() which is not include in current unit-tests.
I have done several tests on those methods and exceptions, which shows that they worked as we excepted.

[Dineshkarthik]

@Lqlsoftware I have cherry-picked your changes and added few more changes along with unit-test to increase code-coverage in PR #63
If you are okay with the other PR we can close this and merge the other one.

[Lqlsoftware]

Ok! I will close this pr. Great work, man.