fix(ensure): packages.Load().Module is nil

[eliottness]

Fixes #371

See golang/go#65816

[codecov]

Codecov Report

Attention: Patch coverage is 70.58824% with 5 lines in your changes missing coverage. Please review.

Project coverage is 58.91%. Comparing base (35b17c0) to head (8200d88).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/ensure/requiredversion.go	0.00%	2 Missing and 1 partial ⚠️
internal/pin/pin.go	85.71%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #372      +/-   ##
==========================================
- Coverage   59.21%   58.91%   -0.30%     
==========================================
  Files         159      160       +1     
  Lines       11423    11503      +80     
==========================================
+ Hits         6764     6777      +13     
- Misses       4162     4248      +86     
+ Partials      497      478      -19     

Components	Coverage Δ
Generators	76.98% <ø> (ø)
Instruments	88.05% <ø> (ø)
Go Driver	73.13% <ø> (ø)
Toolexec Driver	70.64% <ø> (ø)
Aspects	71.28% <ø> (+0.11%)	⬆️
Injector	73.40% <ø> (+0.07%)	⬆️
Job Server	64.02% <ø> (-3.55%)	⬇️
Integration Test Suite	50.42% <ø> (+0.60%)	⬆️
Other	58.91% <70.58%> (-0.30%)	⬇️

Files with missing lines	Coverage Δ
internal/pin/pin.go	58.25% <85.71%> (-1.37%)	⬇️
internal/ensure/requiredversion.go	67.44% <0.00%> (-4.85%)	⬇️

... and 5 files with indirect coverage changes