Very Minor issue: rvm use inconsistency compared to rvm install

[luke-hill]

Description

When installing a new ruby version, the alias x.y will pull down the version x.y.z according to what the rvm version deems to be the latest version. For example as of 1.29.7 rvm deems the latest value of z in the 2.5 series to be 2.5.3

When switching ruby versions, I'd argue this logic should be similar, but if you have a higher version of 2.5 (Lets say 2.5.5), it should "know" that is the highest version. Not use the hardcoded value that's present.

Steps to reproduce

1. rvm install 2.5 - Installs version 2.5.3 correct logic
2. rvm install 2.5.5
3. rvm use 2.5 - This will use 2.5.3

Expected behavior

3. rvm use 2.5 - This should use 2.5.5

Actual behavior

As described in steps to reproduce

Additional notes

If you have The following rubies installed - 2.5.2, 2.5.4, 2.5.5 - Then run the command rvm use 2.5 An error is thrown, which suggests that the logic is only ever looking for one specific x.y.z version. This should check the rubies you have installed and always select the one with the largest value of z