Change language on banner prompt to activate Idea Hub regarding topics

[aaemnnosttv]

Feature Description

Change language on banner prompt to activate Idea Hub from "relevant to your site's topic" to "relevant to your site's topic(s)"

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Do not alter or remove anything below. The following sections will be managed by moderators only.

Acceptance criteria

• The text in the notification which prompts users to set up Idea Hub should be updated to not be specific to a single topic:

  Set up Idea Hub to get topic suggestions based on unanswered searches that match your site’s topics.

Implementation Brief

• Change

  site-kit-wp/assets/js/components/notifications/IdeaHubModuleNotification.js

  Line 94 in b31f31e

  'Set up Idea Hub to get topic suggestions based on unanswered searches that match your site’s topic.',

  to use "topics" instead of "topic".
• Merge Adjust Idea Hub notification from "topic" to "topics". #3914.

Test Coverage

• N/A

Visual Regression Changes

• N/A

QA Brief

• Visit https://google.github.io/site-kit-wp/storybook/develop/?path=/story/modules-idea-hub-notifications-modulenotification--ready and note the notification text has been updated to end in "topics" not "topic".

Changelog entry

• Update the Idea Hub notification text.

[aaemnnosttv]

to use "topic(s)" instead of "topic".

@tofumatt we decided to use plural only rather than the either/or syntax as mentioned in the ACs.

I'll update the IB+PR accordingly since it's such a tiny change, otherwise IB ✅

[wpdarren]

QA Update: ✅

• Confirmed that the notification text has been updated to end in "topics" not "topic".
• Confirmed this on my test site and on Storybook