Update production assets for 3.0.0 release

Merge pull request mautic#8824 from dennisameling/mautic-3-upgrade-sc…

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Add M3 upgrade script

Beta2 version bump

Merge branch 'staging' into 2.16

Update generated assets

Merge pull request mautic#8591 from mautic/staging

Merge staging branch into release-2.16 for 2.16.1 release

Add hyphen to EXTRA_VERSION for beta

Merge branch 'release-3.0.0-beta' into 3.x

Merge pull request mautic#8440 from mautic/release-2.16

Release 2.16.0

Update generated assets