Update flarum/core version to ^2.0.0-rc.3

Update flarum/core version to ^2.0.0-rc.2

Update flarum/core version to 2.0.0-rc.1

Update for beta.8

Update flarum/core version to 2.0.0-beta.7

Update flarum/core dependency to version 2.0.0-beta.6

chore: Update flarum/core version to ^2.0.0-beta.5

chore: v2.0.0-beta.3

chore: v2.0.0-beta.2

fix: minimum stability beta