parrot-devtools: Decommission Firefox plugin

We will be decommissioning the devtool plugin for Firefox so that we can focus our attention on enhancing the plugin for Chrome

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This issue is stale because it has been open 30 days with no activity. Remove no-issue-activity label or comment or this will be closed in 5 days.

[jamesbateaux]

I hadn't seen this issue before I completed #63
Out of interest is there much extra work to maintain compatibility with Firefox web extensions?

There hasn't been much interest in maintaining a Firefox plugin as all of our usage has been with Chrome. I'm not opposed to supporting it if there's enough interest and contribution from the community. Are you interested in looking into what else is required for maintaining compatibility with Firefox?

[github-actions]

This issue is stale because it has been open 30 days with no activity.