feat(metric_alerts): Bump `MAX_ROLLUP_POINTS` to 10k to support wider date ranges. (#20603)
Alternative to https://github.com/getsentry/sentry/pull/20434. It looks like it's not a huge problem
to just render 10k points in the metric alerts rule builder, so we'd like to just bump this value so
that we can fetch more datapoints. This means that we can fetch (almost) a week worth of 1 minute
datapoints, and that should be enough for our requirements.