fix go versioning

Author: alopez-suse

.github/workflows/unitest.yaml

@@ -11,6 +11,6 @@ jobs:
     - uses: actions/checkout@v2
     - uses: actions/setup-go@v2
       with:
-        go-version: '1.20.3'
+        go-version: '1.22.3'
     - run: |
         ./unitest.sh

go.mod

@@ -1,8 +1,6 @@
 module github.com/neuvector/sigstore-interface
 
-go 1.22.0
-
-toolchain go1.22.3
+go 1.22.3
 
 require (
 	github.com/google/go-containerregistry v0.19.1