Support bridge job via API
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It's not possible to run a manual bridge job (`child_trigger` from the example) via api, it returns 404.
.gitlab-ci.yml example:
```
---
stages:
- child:generate
- child:trigger
child_generate:
stage: child:generate
script:
- echo "generate templates here"
- |
cat > test.yml << EOF
---
stages:
- test
test_job:
stage: test
scripts:
- echo "test"
EOF
child_trigger:
stage: child:trigger
trigger:
strategy: depend
include:
- artifact: test.yml
job: child_generate
rules:
- when: manual
```
curl request example:
```
curl -XPOST --globoff --header "PRIVATE-TOKEN: ${GITLAB_API_ACCESS_TOKEN}" "https://gitlab.com/api/v4/projects/<MYPROJECT>/jobs/<MYJOB>/play"
```
response: `{"message":"404 Not found"}`
### Technical Notes
API should support both both manual and auto bridge jobs
issue
