Clean up BASE_FILTERS and move them into the helper that uses them

In ee/app/assets/javascripts/security_dashboard/store/modules/filters/constants.js, there is a BASE_FILTERS object:

https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/app/assets/javascripts/security_dashboard/store/modules/filters/constants.js#L13-34

This object is used only by ee/app/assets/javascripts/security_dashboard/helpers.js for the allOption property in each of the filter config objects:

https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/app/assets/javascripts/security_dashboard/helpers.js

We should move each entry in BASE_FILTERS directly into the filter config objects. There's no need for them to be in a separate file, in a separate object.

How to verify:

1. Verify that ee/app/assets/javascripts/security_dashboard/store/modules/filters/constants.js no longer has a BASE_FILTERS.

2. Verify that ee/app/assets/javascripts/security_dashboard/helpers.js no longer imports from constants.js, and that each filter object's name has a string rather than a variable name (except for scanner filter, which uses a const declared in the same file).

3. Verify that for the project report (https://gitlab.com/gitlab-org/gitlab/-/security/vulnerability_report/?severity=all), clicking on the "All items" dropdown item for each filter will remove that filter's query param from the querystring (or not add it if it's not present). Because "All items" is the default when no query param exists for a filter, there's no need to save "all items" to the querystring when it's selected. The exception is the status filter, which defaults to "needs triage" and "confirmed", so it needs to add state=all to the querystring when "All items" is clicked.

4. Verify the above for the group report: https://gitlab.com/gitlab-org/gitlab/-/security/vulnerability_report

5. Verify the above for the instance report: https://gitlab.com/-/security/vulnerabilities