Update the build for go get update install (#8)

Update the builds so they work with go 1.18
where the ability for go get update
to install has been removed.

Author: smatzek

.github/workflows/build_test.yaml

@@ -15,7 +15,7 @@ jobs:
       - name: Set up Go 1.x
         uses: actions/setup-go@v2
         with:
-          go-version: ^1.15
+          go-version: ^1.16
         id: go
 
       - name: Check out code into the Go module directory

.github/workflows/publish_release_on_tag.yml

@@ -14,7 +14,7 @@ jobs:
       - name: Set up Go 1.x
         uses: actions/setup-go@v2
         with:
-          go-version: ^1.15
+          go-version: ^1.16
         id: go
 
       - name: Checkout code

Makefile

@@ -1,7 +1,7 @@
 TOOL?=vault-plugin-auth-ibmcloud
 TEST?=$$(go list ./... | grep -v /vendor/)
 EXTERNAL_TOOLS=\
-	github.com/mitchellh/gox
+	github.com/mitchellh/gox@v1.0.1
 BUILD_TAGS?=${TOOL}
 GOFMT_FILES?=$$(find . -name '*.go' | grep -v vendor)
 TEST_ARGS?=./...
@@ -38,7 +38,7 @@ generate:
 bootstrap:
 	@for tool in  $(EXTERNAL_TOOLS) ; do \
 		echo "Installing/Updating $$tool" ; \
-		go get -u $$tool; \
+		go install $$tool; \
 	done
 
 fmtcheck:

go.mod

@@ -1,6 +1,6 @@
 module vault-plugin-auth-ibmcloud
 
-go 1.14
+go 1.16
 
 require (
 	github.com/coreos/go-oidc v2.2.1+incompatible