fix: handle padding error for verification token

[uds5501]

Fixes #6167

Short description of what this resolves:

Throws invalid token error for any base64 error

Checklist

• I have read the Contribution & Best practices Guide and my PR follows them.
• My branch is up-to-date with the Upstream development branch.
• The unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

• All the functions created/modified in this PR contain relevant docstrings.

[codecov]

Codecov Report

Merging #6206 into development will decrease coverage by 0.04%.
The diff coverage is 0%.

@@               Coverage Diff               @@
##           development    #6206      +/-   ##
===============================================
- Coverage        65.99%   65.95%   -0.05%     
===============================================
  Files              288      288              
  Lines            14528    14531       +3     
===============================================
- Hits              9588     9584       -4     
- Misses            4940     4947       +7

Impacted Files	Coverage Δ
app/api/auth.py	23.88% <0%> (-0.28%)	⬇️
app/api/helpers/scheduled_jobs.py	21.6% <0%> (-3.2%)	⬇️

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