Added more tests for adjustable types.

[marvin-hansen]

Describe your changes

Added more tests for adjustable types.

Issue ticket number and link

Code checklist before requesting a review

• I have signed the DCO?
• All tests are passing when running make test?
• No errors or security vulnerabilities are reported by make check?

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[codecov]

Codecov Report

Patch coverage: 91.94% and project coverage change: +3.69% 🎉

Comparison is base (cf6de12) 85.00% compared to head (32b2567) 88.69%.

❗ Current head 32b2567 differs from pull request most recent head 63e1280. Consider uploading reports for the commit 63e1280 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #102      +/-   ##
==========================================
+ Coverage   85.00%   88.69%   +3.69%     
==========================================
  Files         122      122              
  Lines        3107     3211     +104     
==========================================
+ Hits         2641     2848     +207     
+ Misses        466      363     -103     

Files Changed	Coverage Δ
deep_causality/src/extensions/causable/mod.rs	64.86% <20.00%> (-16.62%)	⬇️
...de_types_adjustable/adjustable_space/adjustable.rs	100.00% <100.00%> (+100.00%)	⬆️
...pes_adjustable/adjustable_space_time/adjustable.rs	100.00% <100.00%> (+100.00%)	⬆️
..._types_adjustable/adjustable_space_time/display.rs	100.00% <100.00%> (+100.00%)	⬆️
deep_causality_macros/src/collections.rs	100.00% <100.00%> (ø)

... and 6 files with indirect coverage changes

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