fix(chart): Remove trailing slash from default subPath value

[VietND96]

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Description

fix(chart): Remove trailing slash from default subPath value

Motivation and Context

While waiting for the upstream fix SeleniumHQ/selenium#13353 is picked up in 4.17.0
Remove the trailing slash from the default chart values.yaml to unblock #2075

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.