`.swift-version` ignore patch level and use highest installed version

[vsarunas]

I tried to build Swift Package Manager 6.2 branch. The repository contains a .swift-version file requesting 6.1.0, but I have Swift 6.1.1 installed as the default toolchain.
While trying to build SPM there is unnecessary request to downgrade and match the toolchain to a patch level:

swift-package-manager/.swift-version` uses toolchain version 6.1.0, but it doesn't match any of the installed toolchains. You can install the toolchain with `swiftly install`.

Expected: Swift 6.1.1 is present and installed, should be used instead of trying to force to install 6.1.0.