Issue #4279 Fix case sensitive WSL2 validation check

[alegacy]

Fixes: Issue crc-org#4279

Relates to: Issue crc-org#2131, PR crc-org#2323

Solution/Idea

Enhancing WSL validation check to be case-insensitive to prevent users from attempting to run on an unsupported platform.

Proposed changes

Updated validation check to force toLower(...) on the output of /proc/version prior to searching for the target substring of microsoft.

Testing

Validation check now prevents running on systems running WSL regardless of the capitalization of the word Microsoft.

alegacy@localhost:~/src/go/github.com/crc$ ./out/crc setup
INFO Using bundle path /home/alegacy/.crc/cache/crc_libvirt_0.0.0-unset_amd64.crcbundle 
INFO Checking if running as non-root              
INFO Checking if running inside WSL2              
CRC is unsupported using WSL2

alegacy@localhost:~/src/go/github.com/crc$ cat /proc/version
Linux version 5.15.153.1-microsoft-standard-WSL2 (root@941d701f84f1) (gcc (GCC) 11.2.0, GNU ld (GNU Binutils) 2.37) #1 SMP Fri Mar 29 23:14:13 UTC 2024

[alegacy]

IDE created pull request to the fork instead of the main repo ... closing.