Fix StatusTool related issues on Windows

[malliaridis]

Description

After #2712 the introduced changes were causing file permissions errors on Windows systems.

Solution

This PR extends the required permissions to all files for Windows, allowing it to run wmic without limitations to find and filter processes in the java tests. This permission is not needed when running the StatusTool through the CLI, as the Security Manager is not interfering there.

The error returned in test messages mentions:

access denied ("java.io.FilePermission" "<<ALL FILES>>" "execute")

IMPORTANT: This PR edits the test security policies and grants the execute permission to all files.

Tests

The PR fixes an issue in the PATH filtering logic for determining the classpath on Windows. Since on Windows an escaped backslash (\\) is used, path segments are checked individually instead.

Changes should be backported to branch_9x.

Checklist

Please review the following and check all that apply:

• I have reviewed the guidelines for How to Contribute and my code conforms to the standards described there to the best of my ability.
• I have created a Jira issue and added the issue ID to my pull request title.
• I have given Solr maintainers access to contribute to my PR branch. (optional but recommended, not available for branches on forks living under an organisation)
• I have developed this patch against the main branch.
• I have run ./gradlew check.
• I have added tests for my changes.
• I have added documentation for the Reference Guide

[janhoy]

Looks like a decent change to get tests passing on windows. Thanks.

[epugh]

LGTM