NASA's OSAM-1 (formerly known as Restore-L) mission is planned as a technology demonstrator of robotic servicing [0]. The target is the Landsat 7 satellite; but if the technology is successfully demonstrated by OSAM-1, it might be used for robotic servicing of space telescopes in the future.

Originally targeted to launch in 2020, the project has encountered delays, and NASA is currently aiming for January 2025 as the launch date [1]

[0] https://nexis.gsfc.nasa.gov/OSAM-1.html

[1] https://sma.nasa.gov/docs/default-source/sma-disciplines-and... page 4