[DOCS] Missing TAP snapshot instructions in CONTRIBUTING

[MikeMcC399]

Situation

The CONTRIBUTING document, Development section includes the instruction to run tests:

node . run test

which effectively executes the script

"test": "tap"

Further down in the document, the Test Coverage section, tap is also mentioned.

There is however no reference to snapshots, and no instructions about what to do if tap tests fail because snapshots are outdated after making a change. (I hit this issue preparing PR #8371 and managed to work out what to do on my own.)

Background

From plugin: @tapjs/snapshot deals with TAP snapshots

Suggestion

Add an explanation about tap snapshots to the CONTRIBUTING document and include instructions about how to regenerate them if tests fail due to a snapshot mismatch. For example:

node . run test -- --snapshot

[reggi]

#8435

[MikeMcC399]

• Also docs: update snapshot generation command #8459