Update flutter_map dependency to 6.1.x

[JaffaKetchup]

The next version of flutter_map is coming soon, with breaking changes for all users and plugins!

Expected CHANGELOG: https://github.com/fleaflet/flutter_map/blob/release-prep/CHANGELOG.md
Likely to be merged PR with significant impacts: fleaflet/flutter_map#1615
Release prep PR: fleaflet/flutter_map#1632
New documentation (path liable to change): https://docs.fleaflet.dev/v/v6-1
Expected migration instructions, suitable for most users: https://docs.fleaflet.dev/v/v6-1/getting-started/migrating-to-v6
List of commits since v5 (more to come): fleaflet/flutter_map@v5.0.0...master

[greensopinion]

Thanks for the heads-up @JaffaKetchup

All, we have 4 pull requests to get to 6.0: #169 #177 #182 #184
I have limited time to get this in. It would be really helpful if you could all coordinate, agree on and review a single PR.

[JaffaKetchup]

Just to note, v6.1.0 is now available. @greensopinion I'm happy to try to review one of the PRs, just possibly won't have time today.

[greensopinion]

Thanks Luke!

…

On Thu, Dec 7, 2023 at 11:29 PM Luka S ***@***.***> wrote: Just to note, v6.1.0 is now available. @greensopinion <https://github.com/greensopinion> I'm happy to try to review one of the PRs, just possibly won't have time today. — Reply to this email directly, view it on GitHub <#175 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AEKDQ7SFYMZY3CWHF4XFVXDYIK6VJAVCNFSM6AAAAAA5TFMSTKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTQNBWGY4DEMZYHE> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[greensopinion]

new version published, see example commit to upgrade