Add to changelog the ray direction MSL fix

CHANGELOG.md

@@ -54,6 +54,7 @@ release.
 ### Fixed
 - Fixed LRO MiniRF drivers naif keywords focal to pixel and pixel to focal translations to be correct. [#569](https://github.com/DOI-USGS/ale/pull/569)
 - Bugfix for position and orientation for MSL cameras (driver MslMastcamPds3NaifSpiceDriver). Validated that Nav and Mast LBL files (for both left and right sensor) produce correctly positioned and oriented CSM cameras, that are self-consistent and consistent with a prior DEM for the site. [#580](https://github.com/DOI-USGS/ale/pull/580) 
+- Bug fix for ray direction for MSL. [#589](https://github.com/DOI-USGS/ale/pull/589)
 
 ### Changed
 - Removed the affine6p library and replaced affine6p's affine transformation with a numpy solution [#579](https://github.com/DOI-USGS/ale/pull/579)