ci: remove git from dockerignore

Yosys now uses git submodule for abc and requires git information to be
available and correct before compiling Yosys.

Signed-off-by: Vitor Bandeira <[email protected]>

Author: vvbandeira

.dockerignore

@@ -28,9 +28,5 @@ flow/*.log
 # core dumps
 core*
 
-# git
-.git
-.gitignore
-
 # local dependencies
 dependencies/