Add api docs to pipeline stage deploy end point

[knolleary]

Adds api docs to the pipeline stage deploy end point

[codecov]

Codecov Report

Merging #2838 (2935ae3) into main (bf7c1bf) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #2838   +/-   ##
=======================================
  Coverage   39.76%   39.76%           
=======================================
  Files         556      556           
  Lines       19841    19841           
  Branches     4706     4706           
=======================================
  Hits         7890     7890           
  Misses      11951    11951           

Flag	Coverage Δ
backend	75.52% <ø> (ø)
frontend	2.08% <ø> (ø)

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Files	Coverage Δ
forge/ee/routes/pipeline/index.js	79.81% <ø> (ø)

[Pezmc]

This will need to be rebased to see the test fixes. Will merge after #2818.

[knolleary]

7 test failures related to the pipeline api - although only 1 when I run locally. Regardless... investigating.

[knolleary]

Ah yes - running with -b locally means it only tells me about the first failure 🤦🏻 ... that mystery solved. Still investigating.

[knolleary]

Tests should be fixed. Whilst the schema defaulted to body.sourceSnapshotId being optional, it still expected a request body to be present, even if empty.

[knolleary]

Setting body.required = false seems to really upset fastify and causes issues in completely unrelated routes.

Have changed the approach to specifying the type of body as ['object', 'null'] which appears to keep everyone happy.

[knolleary]

Tests related to this PR all passing... failures related to issues on main persist.

Once they are resolved, will rebase and force push