Dependabot does not maintain v1 branch

[evrardjp]

We need to maintain v1 branch now that main is intended for v2. Dependabot does not seem keen to help us, we need to give him a little nudge. :D

[dharsanb]

Was looking into this. But looks like Dependabot package updates can be targeted to multiple branches but security updates only applies to the default branch.

Docs: link (Indicated on the note).