Disregard variants for now, add eras #6

Job	Run time
sbcl-bin / quicklisp on ubuntu-latest	2m 49s
sbcl-bin / ultralisp on ubuntu-latest	2m 59s
sbcl-bin / quicklisp on windows-latest	5m 15s
sbcl-bin / ultralisp on windows-latest	4m 13s
sbcl-bin / quicklisp on macos-latest	4m 13s
sbcl-bin / ultralisp on macos-latest	4m 46s
ccl-bin/1.12.1 / quicklisp on ubuntu-latest	2m 55s
ccl-bin/1.12.1 / ultralisp on ubuntu-latest	3m 16s
ccl-bin/1.12.1 / quicklisp on macos-latest	3m 56s
ccl-bin/1.12.1 / ultralisp on macos-latest	4m 57s
ecl/21.2.1 / quicklisp on ubuntu-latest	10m 15s
ecl/21.2.1 / ultralisp on ubuntu-latest	10m 51s
ecl/21.2.1 / quicklisp on macos-latest	15m 14s
ecl/21.2.1 / ultralisp on macos-latest	15m 50s
	1h 31m 29s

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