Scan Execution Policy - prevent skip_ci does not work with scheduled scans.
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### Summary
In a Scan execution policy, it is possible to [prevent users from using [skip_ci] to bypass security scans](https://docs.gitlab.com/user/application_security/policies/scan_execution_policies/#skip_ci-type).
It is also possible to [setup scheduled scans](https://docs.gitlab.com/user/application_security/policies/scan_execution_policies/#schedule-rule-type) that will be run daily or weekly.
However when combining these, the skip_ci setting of false is not applied.
### Steps to reproduce
1. Setup a Scan Execution Policy similar to below:
<details>
<summary>Policy yaml</summary>
```
scan_execution_policy:
- name: Daily Scan
description: ''
enabled: true
policy_scope:
projects:
excluding: []
skip_ci:
allowed: false
rules:
- type: schedule
cadence: 0 0 * * *
branch_type: protected
timezone: Etc/UTC
actions:
- scan: secret_detection
```
</details>
2, In a test project create a commit with a commit message that ends with `[skip_ci]`.
3. Apply the daily scan security policy to the test project
4. check-in on it the next day

Notice that non of the scans ran for any of the branches.
The behaviour works as expected if the SEP is set to `triggered` instead of `scheduled`.
### Example Project
- [Skip_CI example project](https://gitlab.com/cmarais_ultimate_group/ticket_work/616282_skip_ci_sep/business/test_project)
### What is the current *bug* behavior?
Users are able to bypass the security scans using [skip_ci] if the security scans are scheduled.
This is not true if the security scans are `triggered`.
### What is the expected *correct* behavior?
The [skip_ci] setting should apply to scheduled scans as it works for triggered scans.
### Relevant logs and/or screenshots
Policy set to `triggered`

Policy set to 'scheduled'

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### Possible fixes
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issue