(REF) SettingsMetadata - Small cleanup to prevent duplicate slashes

[totten]

Overview

Small cleanup to make the path nicer.

Before

If $civicrm_root has a trailing slash (/path/to/civicrm/, then it searches for double-slash /path/to/civicrm//settings).

After

Always has single slash (/path/to/civicrm/settings).

[civibot]

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