SEAB-5951: Add GitHub logo image

[svonworl]

Description
After #1865 was merged, Charles noticed that the GitHub logo image in the "Launch with" block was broken. This happened because said logo image was inadvertently not added by the previous PR. This PR adds it.

Review Instructions
Same checks as #1865

Issue
https://ucsc-cgl.atlassian.net/browse/SEAB-5951

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (9d1e1f9) 40.35% compared to head (ef82d2f) 40.35%.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #1868   +/-   ##
========================================
  Coverage    40.35%   40.35%           
========================================
  Files          367      367           
  Lines        11410    11410           
  Branches      2924     2924           
========================================
  Hits          4605     4605           
- Misses        4484     4485    +1     
+ Partials      2321     2320    -1     

see 1 file with indirect coverage changes

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