autopkgtest fails in hirsute

https://autopkgtest.ubuntu.com/packages/e/earlyoom/hirsute/amd64

https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac/autopkgtest-hirsute/hirsute/amd64/e/earlyoom/20210316_172212_99d3a@/log.gz
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autopkgtest [17:22:00]: test unittest.sh: [-----------------------
missing $GOPATH
autopkgtest [17:22:01]: test unittest.sh: -----------------------]
autopkgtest [17:22:01]: test unittest.sh: - - - - - - - - - - results - - - - - - - - - -
unittest.sh FAIL non-zero exit status 1
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