When using inputs only the first variable ($[[ inputs.varname ]]) is replaced on each line, generating wrong gitlab-ci files
### Summary
When processing inputs on `gitlab-ci` only the first input variable found is replaced, leaving the rest untouched (i.e. if a line contains `$[[ inputs.v1 ]] $[[ inputs.v2 ]] $[[ inputs.v1 ]]` the value after the expansion is `value_of_v1 $[[ inputs.v2 ]] value_of_v1`)
### Steps to reproduce
Create an input file that uses more than one input variable on a rule and see that only the first value is expanded.
### Example Project
https://gitlab.com/stalensoliag/wrong-inputs-processing-poc
### What is the current *bug* behavior?
The expanded pipeline has syntax errors because the variables are not expanded
### What is the expected *correct* behavior?
All the input variables are replaced by ther values.
### Relevant logs and/or screenshots
#### Code on the previous project
`.gitlab-ci.yml`:
```
include:
- local: '/gitlab-ci-dumb-job.yml'
inputs:
main_branch: master
```
`gitlab-ci-dumb-job.yml`:
```
spec:
inputs:
dev_branch:
default: 'develop'
main_branch:
default: 'main'
rel_branch:
default: 'release'
---
dumb_job:
rules:
- if: $CI_COMMIT_BRANCH == "$[[ inputs.dev_branch ]]"
|| $CI_COMMIT_BRANCH == "$[[ inputs.main_branch ]]"
|| $CI_COMMIT_BRANCH == "$[[ inputs.rel_branch ]]"
- when: never
script:
- echo "Dumb job for '$[[ inputs.dev_branch ]]', '$[[ inputs.main_branch ]]' or '$[[ inputs.rel_branch ]]'"
- echo "Testing if we put the same input two times '$[[ inputs.dev_branch ]]' & '$[[ inputs.dev_branch ]]'"
stage: test
```
#### Message from the pipeline
```Unable to create pipeline jobs:dumb_job:rules:rule if invalid expression syntax```
#### Full configuration from the pipeline editor
```
---
dumb_job:
rules:
- if: $CI_COMMIT_BRANCH == "develop" || $CI_COMMIT_BRANCH == "$[[ inputs.main_branch ]]" || $CI_COMMIT_BRANCH == "$[[ inputs.rel_branch ]]"
- when: never
script:
- echo "Dumb job for 'develop', '$[[ inputs.main_branch ]]' or '$[[ inputs.rel_branch ]]'"
- echo "Testing if we put the same input two times 'develop' & 'develop'"
stage: test
```
As you can see neither `main_branch` nor `rel_branch` inputs have been expanded.
### Output of checks
This bug happens on GitLab.com
issue