common/options/global.yaml.in: increase default value of bluestore_cache_trim_max_ski...

common/options/global.yaml.in: increase default value of bluestore_cache_trim_max_skip_pinned

This option controls the rate of trimming of onodes and the earlier default of
64 has been seen to be too low for large clusters, leading to buildup of
onodes resulting in memory growth.

Increase the default value to 1000, since there are no known downsides to it.

Fixes: https://tracker.ceph.com/issues/50217
Signed-off-by: Neha Ojha <nojha@redhat.com>