Fix incorrect path resolution for system profile under WOW64 (x86) redirection

[fp024]

When MAVEN_M2_PATH points to a Windows system profile path (e.g., C:\Windows\System32\config\systemprofile\.m2),
running under an x86 (WOW64) process causes the path to be redirected to C:\Windows\SysWOW64\config\systemprofile\.m2.
In this case, (Get-Item -Path $MAVEN_M2_PATH -Force).Target returns $null instead of an array.

The previous code accessed .Target[0] directly, which throws an error when .Target is $null under an x86 process.

This fix stores .Target in a variable first and checks its type before indexing.

• Issue: mvnw.cmd crashes with "Cannot index into a null array" on 32-bit System Profile path (Jenkins service) #395
• See also: https://github.com/fp024/win-file-link-test/blob/main/README_en.md

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[fp024]

Hi,
Verified the behavior before and after the fix by installing Jenkins 2.541.2 on a Windows Server 2022 x64 180-day evaluation edition.

• https://github.com/fp024/win-file-link-test/blob/main/jenkins-test_en.md

Please take a look. Thank you. 👍