Revert "promql: Remove unused Point.MarshalJSON method (#9860)" (#9864)
Revert "promql: Remove unused Point.MarshalJSON method (#9860)" (#9864)

This reverts commit 427425cc9f477db22a8b3b1e832c965033322a44.

Signed-off-by: Ganesh Vernekar <101acfd19ae0f3f87f861c64d0a8873056704c2b@gmail.com>
keegancsmith/prometheus,keegancsmith/prometheus,keegancsmith/prometheus,keegancsmith/prometheus,prometheus/prometheus,prometheus/prometheus,prometheus/prometheus,keegancsmith/prometheus,prometheus/prometheus,prometheus/prometheus