Added adaptive timestepping

[RemDelaporteMathurin]

Fix for #992

[codecov]

Codecov Report

❌ Patch coverage is 33.33333% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 95.40%. Comparing base (bedbb20) to head (b30c5a1).
⚠️ Report is 165 commits behind head on fenicsx.

Files with missing lines	Patch %	Lines
src/festim/hydrogen_transport_problem.py	33.33%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           fenicsx     #993      +/-   ##
===========================================
- Coverage    95.43%   95.40%   -0.04%     
===========================================
  Files           46       46              
  Lines         2847     2848       +1     
===========================================
  Hits          2717     2717              
- Misses         130      131       +1     

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