Dockerfile: Remove brew tests
Dockerfile: Remove brew tests

Two tests fail.

1) Failure:
IntegrationCommandTests#test_uses [/home/linuxbrew/.linuxbrew/Library/Homebrew/test/test_integration_cmds.rb:629]:
--- expected
+++ actual
@@ -1,2 +1,2 @@
-"testball1
-testball2"
+"testball2
+testball1"

2) Failure:
LanguageModuleRequirementTests#test_good_python_deps [/home/linuxbrew/.linuxbrew/Library/Homebrew/test/test_language_module_requirement.rb:43]:
Expected #<LanguageModuleRequirement: "languagemodule" [:python, "datetime", nil]>
to be satisfied?.
840 runs, 2015 assertions, 2 failures, 0 errors, 6 skips

Angeldude/linuxbrew,sjackman/linuxbrew,Angeldude/linuxbrew,reelsense/linuxbrew,reelsense/linuxbrew,Linuxbrew/linuxbrew,Linuxbrew/linuxbrew,DoomHammer/linuxbrew,saketkc/linuxbrew,Linuxbrew/linuxbrew,Angeldude/linuxbrew,drbenmorgan/linuxbrew,Homebrew/linuxbrew,Angeldude/linuxbrew,sjackman/linuxbrew,SuperNEMO-DBD/cadfaelbrew,Homebrew/linuxbrew,Linuxbrew/linuxbrew,drbenmorgan/linuxbrew,saketkc/linuxbrew,sjackman/linuxbrew,Homebrew/linuxbrew,DoomHammer/linuxbrew,saketkc/linuxbrew,DoomHammer/linuxbrew,saketkc/linuxbrew,drbenmorgan/linuxbrew,Homebrew/linuxbrew,SuperNEMO-DBD/cadfaelbrew,DoomHammer/linuxbrew,reelsense/linuxbrew,SuperNEMO-DBD/cadfaelbrew,SuperNEMO-DBD/cadfaelbrew,gnubila-france/linuxbrew,sjackman/linuxbrew,drbenmorgan/linuxbrew,gnubila-france/linuxbrew,gnubila-france/linuxbrew,reelsense/linuxbrew,gnubila-france/linuxbrew