Feature Request: respect value in $TERM for buck2 server command

[spew]

In a CI system it is often desired that all console output is printed without colors. This can usually be achieved with setting TERM to dumb in the environment. The buck2 build command respects the TERM variable and disables all color printing, however, the buck2 server command does not.

Task is for buck2 server at minimum to turn off color printing when the TERM value is set to dumb.