Bugfix - make sure messaging is done immediately after an SDR granule is ready

[adybbroe]

Bugfix - make sure messaging is done immediately after an SDR granule is ready.

Clean up, re-factor and fix so messages are being sent immediately when SDR granule is ready

• Closes #xxxx
• Tests added
• Tests passed: Passes pytest cspp_runner
• Passes flake8
• Fully documented

[codecov]

Codecov Report

Merging #28 (be3c85a) into main (6f22cca) will decrease coverage by 0.08%.
The diff coverage is 88.10%.

❗ Current head be3c85a differs from pull request most recent head 705a08b. Consider uploading reports for the commit 705a08b to get more accurate results

@@            Coverage Diff             @@
##             main      #28      +/-   ##
==========================================
- Coverage   78.59%   78.51%   -0.08%     
==========================================
  Files          12       13       +1     
  Lines         995     1117     +122     
==========================================
+ Hits          782      877      +95     
- Misses        213      240      +27     

Flag	Coverage Δ
unittests	78.51% <88.10%> (-0.08%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
cspp_runner/viirs_dr_runner.py	96.61% <ø> (-0.06%)	⬇️
cspp_runner/post_cspp.py	68.42% <80.88%> (-0.19%)	⬇️
cspp_runner/runner.py	82.81% <82.22%> (-2.17%)	⬇️
cspp_runner/tests/test_runner.py	99.17% <97.77%> (+0.19%)	⬆️
cspp_runner/tests/conftest.py	100.00% <100.00%> (ø)
cspp_runner/tests/test_post_cspp.py	100.00% <100.00%> (ø)

... and 1 file with indirect coverage changes