[CI] refcache refresh and adjust prune Gulp task

[chalin]

• Contributes to [CI] External link checking improvements for 24H2-25H1 #5017
• Adjusts prune Gulp task to better handle defaults
• Refreshes a few hundred refcache entries
• I'm going to also test the fix refcache:refresh PR action here, so marking this as draft in the meantime.

[chalin]

/fix:refcache:refresh

[opentelemetrybot]

You triggered fix:refcache:refresh action run at https://github.com/open-telemetry/opentelemetry.io/actions/runs/12752241140

[opentelemetrybot]

fix:refcache:refresh failed or was cancelled. For details, see https://github.com/open-telemetry/opentelemetry.io/actions/runs/12752241140.

[chalin]

/fix:refcache:refresh

[opentelemetrybot]

You triggered fix:refcache:refresh action run at https://github.com/open-telemetry/opentelemetry.io/actions/runs/12752815835

[opentelemetrybot]

fix:refcache:refresh failed or was cancelled. For details, see https://github.com/open-telemetry/opentelemetry.io/actions/runs/12752815835.

[chalin]

/fix:refcache:refresh

[opentelemetrybot]

You triggered fix:refcache:refresh action run at https://github.com/open-telemetry/opentelemetry.io/actions/runs/12757206613

[opentelemetrybot]

fix:refcache:refresh failed or was cancelled. For details, see https://github.com/open-telemetry/opentelemetry.io/actions/runs/12757206613.

[chalin]

/fix:refcache

[opentelemetrybot]

You triggered fix:refcache action run at https://github.com/open-telemetry/opentelemetry.io/actions/runs/12771247957

[opentelemetrybot]

fix:refcache was successful.

IMPORTANT: (RE-)RUN /fix:all to ensure that there are no remaining check issues.

[tiffany76]

RSLGTM.