chore: audit testutil

[blushi]

Description

Ref: #11362

---

Author Checklist

All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.

I have...

• included the correct type prefix in the PR title
• added ! to the type prefix if API or client breaking change
• targeted the correct branch (see PR Targeting)
• provided a link to the relevant issue or specification
• followed the guidelines for building modules
• included the necessary unit and integration tests
• added a changelog entry to CHANGELOG.md
• included comments for documenting Go code
• updated the relevant documentation or specification
• reviewed "Files changed" and left comments if necessary
• confirmed all CI checks have passed

Reviewers Checklist

All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.

I have...

• confirmed the correct type prefix in the PR title
• confirmed ! in the type prefix if API or client breaking change
• confirmed all author checklist items have been addressed
• reviewed state machine logic
• reviewed API design and naming
• reviewed documentation is accurate
• reviewed tests and test coverage
• manually tested (if applicable)

[codecov]

Codecov Report

Merging #11954 (af4f013) into main (7a31a28) will decrease coverage by 0.30%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main   #11954      +/-   ##
==========================================
- Coverage   66.28%   65.98%   -0.31%     
==========================================
  Files         690      677      -13     
  Lines       72282    71329     -953     
==========================================
- Hits        47910    47063     -847     
+ Misses      21665    21583      -82     
+ Partials     2707     2683      -24     

Impacted Files	Coverage Δ
testutil/mock/privval.go	70.00% <ø> (ø)
testutil/network/network.go	62.40% <ø> (ø)
testutil/network/util.go	66.66% <0.00%> (-0.91%)	⬇️
container/struct_args.go
container/provider_desc.go
container/module_dep.go
container/container.go
container/simple.go
container/group.go
... and 11 more

[julienrbrt]

lgtm

[amaury1093]

lgtm, i also prefer returning an error than panicking