Add dockerfile linting #523

Job	Run time
Linting	23s
Test Windows (2.7)	1m 11s
Test Windows (3.11)	46s
Test Windows (3.7)	1m 4s
Test Windows (3.8)	1m 25s
Test (python2.7)	14s
Test Windows (3.6)	1m 7s
Test Windows (3.13)	41s
Test Windows (3.12)	58s
Test (python3.5)	15s
Test Windows (3.9)	39s
Test (python3.3)	17s
Test (python3.7)	11s
Test (python3.6)	12s
Test (python3.4)	12s
Test (python3.11)	24s
Test Windows (3.10)	58s
Lint Dockerfiles (Dockerfile-fedora28)	9s
Test (python3.13)	21s
Test (python3.8)	13s
Test (pypy)	13s
Test (pypy3)	11s
Test (python3.9)	21s
Lint Dockerfiles (Dockerfile-fedora38)	9s
Lint Dockerfiles (Dockerfile-fedora40)	10s
Lint Dockerfiles (Dockerfile-fedora36)	11s
Lint Dockerfiles (Dockerfile-fedora34)	10s
Test (python3.12)	23s
Lint Dockerfiles (Dockerfile-fuzz)	13s
Lint Dockerfiles (Dockerfile-fedora30)	7s
Test (python3.10)	24s
Lint Dockerfiles (Dockerfile-fedora32)	10s
	14m 22s

Provide feedback