Use i18n text on Tooltips

[ann-kilzer]

Follow up from #177 and this PR.

Add i18n to the "Facebook", "Twitter," etc. raw text so we can adjust the eslint warning

<!--eslint-disable-next-line @intlify/vue-i18n/no-raw-text -->

Note it's okay to use this exception around the <v-icon> tags because icons are keyed on text, and we don't want to translate it. But since the tooltips are human-readable text, we want to enable translations, and therefore we don't want to disable the warning on these lines

Here's the file where the changes should be made:
web/src/components/speaker/Links.vue

And here's the documentation for how vue i18n works: https://kazupon.github.io/vue-i18n/guide/formatting.html#named-formatting