Revert "build: fail nicely if somebody runs all.bash from a binary tarball package"
Revert "build: fail nicely if somebody runs all.bash from a binary tarball package"

This reverts commit 3d86d45dd60358636c569e9cf06b23b5e0e04e8a.

Reason for revert: Fixing a different way. See #20008.

Change-Id: I6f4382ffdfff83a4504b013ba37100319b2c1aad
Reviewed-on: https://go-review.googlesource.com/42138
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

codestation/go,cloudflare/go,nawawi/go,polyverse-security/go,vsekhar/elastic-go,josharian/go,golang/go,akutz/go,codestation/go,polyverse-security/go,vsekhar/elastic-go,ImJasonH/go,cloudflare/go,ImJasonH/go,CAFxX/go,josharian/go,nawawi/go,codestation/go,josharian/go,golang/go,Cofyc/go,vsekhar/elastic-go,codestation/go,ImJasonH/go,cloudflare/go,CAFxX/go,akutz/go,vsekhar/elastic-go,vsekhar/elastic-go,CAFxX/go,nawawi/go,derekmarcotte/go,Cofyc/go,akutz/go,Cofyc/go,josharian/go,vsekhar/elastic-go,derekmarcotte/go,ImJasonH/go,derekmarcotte/go,golang/go,CAFxX/go,ImJasonH/go,nawawi/go,cloudflare/go,ImJasonH/go,cloudflare/go,polyverse-security/go,golang/go,akutz/go,codestation/go,Cofyc/go,polyverse-security/go,Cofyc/go,derekmarcotte/go,akutz/go,josharian/go,codestation/go,polyverse-security/go,akutz/go,akutz/go,golang/go,CAFxX/go,vsekhar/elastic-go,CAFxX/go,Cofyc/go,golang/go,Cofyc/go,polyverse-security/go,codestation/go,Cofyc/go,ImJasonH/go,christopher-henderson/Go,nawawi/go,golang/go,derekmarcotte/go,josharian/go,ImJasonH/go,derekmarcotte/go,codestation/go,akutz/go,CAFxX/go,derekmarcotte/go,cloudflare/go,nawawi/go,vsekhar/elastic-go,cloudflare/go,nawawi/go,josharian/go,polyverse-security/go,nawawi/go,polyverse-security/go,derekmarcotte/go,CAFxX/go,golang/go,josharian/go,cloudflare/go