Adjust version hash

[josephjclark]

To better align version hashing between lightning and CLI, I've made some changes

• lowercase step names
• remove keys from the hash string

These are not breaking

Closes #4346

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[codecov]

Codecov Report

❌ Patch coverage is 81.81818% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.32%. Comparing base (549de66) to head (33e58de).

Files with missing lines	Patch %	Lines
lib/lightning/workflow_versions.ex	81.81%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4349      +/-   ##
==========================================
+ Coverage   89.29%   89.32%   +0.02%     
==========================================
  Files         425      425              
  Lines       19994    19997       +3     
==========================================
+ Hits        17854    17862       +8     
+ Misses       2140     2135       -5     

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