schema_salad 7.1.20210611090601 ; fixed resolution examples & dependency updates

Fix resolution examples (#394) 8d18419 @tom-tan

ruamel.yaml up to 0.18 1f2ce96 065cdda 19c2d1c @mvdbeek @mr-c @dependabot
Update pytest requirement from <6.2,>=6.0.2 to >=6.0.2,<6.3 3bf3be3 @mr-c @dependabot
Bump mypy from 0.812 to 0.902 b43fb2c 2cc8a93 1ed0ef4 @mr-c @dependabot
Bump cachecontrol from 0.11.7 to 0.12.6 f877373 @dependabot @mr-c