Mismatching `processID`/`process` URI between Part 1 / Part 3 execution request

[fmigneault]

ogcapi-processes/openapi/schemas/processes-core/execute.yaml

Line 3 in 33f775d

processID:

mismatched against

ogcapi-processes/openapi/schemas/processes-workflows/execute-workflows.yaml

Line 4 in 33f775d

process:

As mentioned in #480 (comment), it was expected to be changed to process, but the change was not applied.