Add explanatory tooltips on the pictos for the revision history

When browsing the history of revisions, some revisions are shown with a tag lable, other with a commit label, and there is no clear meaning shown. See for example: https://archive.softwareheritage.org/browse/origin/https://github.com/scilab/scilab/releases/

For readability, we need explanatory tooltips that explain what each picto means.

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Migrated from T1751 (view on Phabricator)