Add humanize support for branch types for security policies

What does this MR do and why?

Add humanize support for branch types for security policies

• Add humanize support for branch types
• branch types are now supported for humanized messages for scan result policy
• add no rule message for invalid branch types
• make humanize code similar for future consolidation

Changelog: added

EE: true

What does this MR not do and why?

• it does not abstract out some of the humanize methods because our file structure is not set up for this...yet. There are plans to look into it with #417691 (comment 1469201036)

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

Policy Type	yaml	Before	After
Scan Execution	type: pipeline, branch_type: all	-	Every time a pipeline runs for any branch
Scan Execution	type: pipeline, branches: ["*"]	on every pipeline on the * branch	Every time a pipeline runs for the * branch
Scan Execution	type: pipeline, branches: [production, staging, release/*]	on every pipeline on the production, staging and release/* branches	Every time a pipeline runs for the production, staging and release/* branches
Scan Execution	type: pipeline, branch_type: protected	-	Every time a pipeline runs for any protected branch
Scan Execution	type: schedule, cadence: 0 0 * * *, branch_type: default	-	at 12:00 am, every day on the default branch
Scan Result	branch_type: protected	-	When Container Scanning scanner finds more than 5 vulnerabilities in an open merge request targeting any protected branch and all the following apply:
Scan Result	branch_type: default	-	When license scanner finds any license matching MIT License that is newly detected and is in an open merge request targeting the default branch.
Scan Result	branches: spooky-stuff	When license scanner finds any license except Apache License 2.0 that is pre-existing and is in an open merge request targeting the spooky-stuff branch.	No change

Policy Type	Screenshot
Scan Execution
Scan Result

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. Upload an GitLab Ultimate license
2. Navigate to a group/project => Secure => Policies => New policy => Scan Execution Policy
3. Create a policy with a variety of branch types
4. Navigate to a group/project => Secure => Policies and verify the drawer for those new policies
5. Navigate to a group/project => Secure => Policies => New policy => Scan Result Policy
6. Create a policy with a variety of branch types
7. Navigate to a group/project => Secure => Policies and verify the drawer for those new policies

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #404778 (closed)