fix prefix match error

[zhylmzr]

PS C:\Users\zhylmzr> vfox --version
vfox version 0.4.0
PS C:\Users\zhylmzr> vfox u golang
Please select a version of golang:
  -> 1.22.2
golang@ is not installed

fix #225

[aooohan]

Thanks for the PR, I modified it a little bit.

[Chance-fyi]

The fix is not quite correct; if the following versions are available:

golang 1.22.2
golang 1.2.1

vfox use golang@1.2 will match 1.22.2.

[aooohan]

The fix is not quite correct; if the following versions are available:

golang 1.22.2
golang 1.2.1

vfox use golang@1.2 will match 1.22.2.

This still needs to be optimized, so let's leave it for 0.4.2. For now, let's make sure that the previous behavior is not broken.