fix: nil deref in usage of incomplete experiment config policies

[stoksc]

Ticket

CM-572

Description

Fix a call to cfg.Resources().Priority() on an experiment config without schemas.WithDefaults. I didn't call with defaults because the config is intentionally incomplete (we need to know what the user set, without any defaulting).

Test Plan

Manually tested.

Checklist

• Changes have been manually QA'd
• New features have been approved by the corresponding PM
• User-facing API changes have the "User-facing API Change" label
• Release notes have been added as a separate file under docs/release-notes/
  See Release Note for details.
• Licenses have been included for new code which was copied and/or modified from any external code

[netlify]

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[amandavialva01]

LGTM, great work!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 54.44%. Comparing base (6c46a46) to head (87de272).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10068      +/-   ##
==========================================
+ Coverage   54.42%   54.44%   +0.02%     
==========================================
  Files        1262     1262              
  Lines      158901   158901              
  Branches     3631     3631              
==========================================
+ Hits        86476    86509      +33     
+ Misses      72291    72258      -33     
  Partials      134      134              

Flag	Coverage Δ
backend	45.56% <100.00%> (+0.06%)	⬆️
harness	72.74% <ø> (ø)
web	53.95% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
master/internal/configpolicy/task_config_policy.go	87.16% <100.00%> (ø)

... and 9 files with indirect coverage changes