fix(instrumentation): only patch core modules if enabled

[santigimeno]

Which problem is this PR solving?

Otherwise, disabling the instrumentation module before actually
requiring the to-be-instrumented module doesn't work, and the module is
patched.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

• Existing tests pass.

Checklist:

• Followed the style guidelines of this project
• Unit tests have been added
• Documentation has been updated

[codecov]

Codecov Report

Merging #2993 (e8c65da) into main (eda0b09) will increase coverage by 0.06%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #2993      +/-   ##
==========================================
+ Coverage   92.71%   92.77%   +0.06%     
==========================================
  Files         183      183              
  Lines        6134     6135       +1     
  Branches     1299     1300       +1     
==========================================
+ Hits         5687     5692       +5     
+ Misses        447      443       -4     

Impacted Files	Coverage Δ
...strumentation/src/platform/node/instrumentation.ts	63.21% <100.00%> (+5.07%)	⬆️

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: santigimeno / name: Santiago Gimeno (68e1caa)

[dyladan]

Lint failure not caused by this pull request