Version showing incorrectly

[chenilim]

Summary:
The version is displayed as 0.6.0 even in the 0.6.1 build

Steps to reproduce the behavior:

1. Install 0.6.1 and open web app
2. Version shows 0.6.0

Expected behavior:
Show 0.6.1

Platform:

• Chrom 89 on macOS 10.15.7

Additional context:
Even though this is just cosmetic, we should fix this to make consistent future updates easier. At the moment, the version string is hardcoded in several places:

• webapp/src/constants.ts (this is the one displayed by the webapp)
• webapp/package.json (not actually used)
• server/model/version.go (this is displayed by the server at boot)
• mac/Focalboard/Info.plist (used by the Mac app)
• win-wpf/AppxManifest.xml (used by the Windows app)

Ideally, this should be stamped at build-time, but for now, let's keep them in sync manually.

[chenilim]

Additional note for the future: Technically, the server can and should have an independent version from the clients.