Tests

Use Chocolatey to install bzip2.dll for Windows tests in CI. #40

Job	Run time
test (ubuntu, 3.1)	11s
test (ubuntu, 3.0)	14s
test (ubuntu, 3.3)	28s
test (ubuntu, 3.4)	25s
test (ubuntu, head)	9s
test (ubuntu, 3.2)	18s
test (ubuntu, jruby-head)	1m 8s
test (ubuntu, jruby)	1m 5s
test (ubuntu, truffleruby-head)	26s
test (ubuntu, truffleruby)	26s
test (windows, 3.0)	1m 2s
test (macos, 3.0)	18s
finish	6s
	6m 16s

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