Update unzip version (github#12)

* Update unzip version

It looks like 6.0-26 is no longer available due to a security problem.

* Try unpinned unzip

* Use unzip 6.0-26+deb11u1

Use install > get as it will stop building bins (github#9)

Though at this point we still use Go 1.17, 1.18 release notes say: 

> go get no longer builds or installs packages in module-aware mode

Ref: https://tip.golang.org/doc/go1.18

Update go, protoc, protoc-gen-twirp

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