Update circular text to include CGMI information

Releasing coarse-grained mass information has been proposed in the form of probabilities in a range of pre-determined bins. The circular text should include mention of either the most probable bin or possibly each bin with probability above a certain value.

Here is the issue: https://git.ligo.org/publications/o4/cbc/task_forces/-/issues/6

code: https://git.ligo.org/emfollow/em-properties/cgmi_chirp_mass_bins

and schema changes: igwn-gwalert-schema!2