build last 2 versions of go

Signed-off-by: Dan Bond <danbond@protonmail.com>

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
     - uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # pin@v3.3.0
     - uses: actions/setup-go@6edd4406fa81c3da01a34fa6f6343087c207a568 # pin@v3.5.0
       with:
-        go-version-file: 'go.mod'
+        go-version: '1.20'
         cache: true
     - run: |
         files=$(go fmt ./...)
@@ -31,6 +31,7 @@ jobs:
     needs: go-fmt-and-vet
     strategy:
       matrix:
+        arch: ['1.19', '1.20']
         arch: ['x32', 'x64']
     runs-on: ubuntu-22.04
     env:
@@ -39,7 +40,7 @@ jobs:
     - uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # pin@v3.3.0
     - uses: actions/setup-go@6edd4406fa81c3da01a34fa6f6343087c207a568 # pin@v3.5.0
       with:
-        go-version-file: 'go.mod'
+        go-version: ${{ matrix.go }}
         architecture: ${{ matrix.arch }}
         cache: true
     # x86 specific build.

go.mod

@@ -1,6 +1,6 @@
 module github.com/hashicorp/raft
 
-go 1.20
+go 1.16
 
 retract v1.1.3 // Deleted original tag; module checksum may not be accurate.
 
@@ -10,10 +10,3 @@ require (
 	github.com/hashicorp/go-msgpack v0.5.5
 	github.com/stretchr/testify v1.3.0
 )
-
-require (
-	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/hashicorp/go-immutable-radix v1.0.0 // indirect
-	github.com/hashicorp/golang-lru v0.5.0 // indirect
-	github.com/pmezard/go-difflib v1.0.0 // indirect
-)