[chore] Fix some transient dependencies

[dej611]

PR Checklist

• My branch is up-to-date with the Upstream master branch.
• The unit tests pass locally with my changes (if applicable).
• I have added tests that prove my fix is effective or that my feature works (if applicable).
• I have added necessary documentation (if appropriate).

Short description of what this resolves:

Added some transient dependencies which were not properly declared:

• is-number used by Input component but not declared
• classnames used by various components but not declared
• bootstrap-italia used by the kit itself (Resizer) but not declared as peerDep

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