[JENKINS-75012] Pre-compile Handlebars templates

[yaroslavafenkin]

https://issues.jenkins.io/browse/JENKINS-75012

All of the Handlebars stuff is now pre-compiled in built time instead of run time. This includes templates, partials and helpers.

Depends on #122. I'll rebase this PR when that one is merged.

Testing done

There's not much to show in "Before". In report-only mode 15+ violations are caught coming from handlebars-2.0.0.js because of runtime template compilation. In restrictive mode page doesn't render at all.

After the change

Proposed upgrade guidelines

N/A

Submitter checklist

• The Jira / Github issue, if it exists, is well-described.
• The changelog entries and upgrade guidelines are appropriate for the audience affected by the change (users or developers, depending on the change) and are in the imperative mood (see examples).
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• There is automated testing or an explanation that explains why this change has no tests.
• New public functions for internal use only are annotated with @NoExternalUse. In case it is used by non java code the Used by {@code <panel>.jelly} Javadocs are annotated.
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Maintainer checklist

Before the changes are marked as ready-for-merge:

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[yaroslavafenkin]

I feel I haven't tested this enough yet. Also in the end of the recoding an img-src violation shows up, so I'll try to investigate it a bit.

[yaroslavafenkin]

img-src violation in console:

Triggered by clicking "Download PNG image" on a chart hamburger dropdown.

Seems to be coming from highchart-exporting.js. Does not affect any of the functionalities on the Test Results Analyzer view.