fix noscript allow-once for selective scripts

[diracdeltas]

fix #9150

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.

Test Plan:
1. block scripts globally
2. go to twitter.com
3. click the noscript icon, make sure only 'twitter.com' is checked, click 'allow once'
4. close the tab
5. open twitter.com in a new tab
3. click the noscript icon. 'twitter.com' should appear in the list.

Reviewer Checklist:

Tests

• Adequate test coverage exists to prevent regressions
• Tests should be independent and work correctly when run individually or as a suite ref
• New files have MPL2 license header

[luixxiul]

If you set twitter.com as a new tab, the setting does not seem to be cleared by opening a new tab.

STR:

1. Set https://www.twitter.com to your home page
2. Open a new tab
3. Click the noscript icon
4. Click "allow this time"
5. Open a new tab

Actual result: there does not appear the noscript icon. If you close the tab and open a new tab, then the icon appears again.

Expected result: the icon should appear on each new tab

[luixxiul]

feedback left.

[diracdeltas]

@luixxiul the setting is expired when the tab closes, so it is expected that the noscript icon only appears again after a twitter tab has been closed