treewide get rid of go 1.12 (#83253)

* treewide Drop unneeded go 1.12 overrides

* Fix packr to be go module compatible.

I updated to version 2.8.0 which is the latest on master.
Then due to the 2 different sets of go modules which are used, I split
the build into two different derivations, then merged them togethor
using symlinkJoin to have the same output structure as the existing derivation.

* Remove consul dependency on go1.12

I updated the consul version to 1.7.2 and flipped it to building using
modules.

* Remove go1.12 from perkeep.

Update the version to the latest unstable on master.

* Update scaleway-cli to not be pinned to go1.12

Switched the version to 1.20

* Update prometheus-varnish-exporter to not depend on go1.12

* Update lnd to build with go1.12

Updated the version
Forced only building subpackages with main to prevent panics over
multiple modules in one repo

* Remove go1.12 from openshift

Had to update the version to 4.1.0 and do a bit of munging to get this
to work

* Remove go1.12 completely.

These are no longer needed.

* Update bazel-watcher and make it build with go 1.14

pkgs/servers/monitoring/prometheus/varnish-exporter.nix

@@ -2,16 +2,16 @@
 
 buildGoModule rec {
   pname = "prometheus_varnish_exporter";
-  version = "1.5.2";
+  version = "unstable-2020-03-26";
 
   src = fetchFromGitHub {
     owner = "jonnenauha";
     repo = "prometheus_varnish_exporter";
-    rev = version;
-    sha256 = "0rpabw6a6paavv62f0gzhax9brzcgkly27rhkf0ihw8736gkw8ar";
+    rev = "f0f90fc69723de8b716cda16cb419e8a025130ff";
+    sha256 = "1viiiyvhpr7cnf8ykaaq4fzgg9xvn4hnlhv7cagy3jkjlmz60947";
   };
 
-  modSha256 = "0w1zg9jc2466srx9pdckw7rzn7ma4pbd0617b1h98v364wjzgj72";
+  modSha256 = "1vb720axjziiqcba4bdi528r6mc97ci0pfsk0ny50isrkh0s3jzz";
 
   nativeBuildInputs = [ makeWrapper ];