Add parameter to only optionally refresh the schema hash on schema.all

[ogenstad]

The goal of this PR is primarily for use within computed attributes, currently for the Jinja2 template based computed attributes we are constantly refreshing the schema of the SDK for each attribute. This is because we have no way of knowing if the schema in the client is up to date or if a branch we'd previously cashed has updates. With this in place we can send in the current hash stored in the registry to the schema.all method and only call the /api/schema endpoint if any updates have actually been made.

As a follow up to this PR I'm thinking that we should mark the public schema.fetch() method as deprecated. I don't think anyone uses it and instead use schema.get() or schema.all().

Fixes #152.

[codecov]

Codecov Report

Attention: Patch coverage is 94.44444% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
infrahub_sdk/schema/__init__.py	93.75%	2 Missing ⚠️

@@             Coverage Diff             @@
##           develop     #310      +/-   ##
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+ Coverage    70.64%   71.32%   +0.67%     
===========================================
  Files           81       87       +6     
  Lines         7499     7871     +372     
  Branches      1457     1517      +60     
===========================================
+ Hits          5298     5614     +316     
- Misses        1818     1865      +47     
- Partials       383      392       +9     

Flag	Coverage Δ
integration-tests	22.80% <22.22%> (+0.14%)	⬆️
python-3.10	45.45% <77.77%> (-0.11%)	⬇️
python-3.11	45.48% <77.77%> (-0.09%)	⬇️
python-3.12	45.48% <77.77%> (-0.09%)	⬇️
python-3.13	45.45% <77.77%> (?)
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Files with missing lines	Coverage Δ
infrahub_sdk/schema/main.py	84.04% <100.00%> (+0.57%)	⬆️
infrahub_sdk/schema/__init__.py	70.06% <93.75%> (+2.05%)	⬆️

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[dgarros]

LGTM
Not sure about marking fetch as deprecated ... it's probably not used extensively but it could be useful.