Update golang to 1.18.5

Update Go runtime to 1.18.5 to address CVE-2022-32189.

Full diff: https://github.com/golang/go/compare/go1.18.4...go1.18.5

--------------------------------------------------------

From the security announcement:
https://groups.google.com/g/golang-announce/c/YqYYG87xB10

We have just released Go versions 1.18.5 and 1.17.13, minor point
releases.

These minor releases include 1 security fixes following the security
policy:

encoding/gob & math/big: decoding big.Float and big.Rat can panic

Decoding big.Float and big.Rat types can panic if the encoded message is
too short.

This is CVE-2022-32189 and Go issue https://go.dev/issue/53871.

View the release notes for more information:
https://go.dev/doc/devel/release#go1.18.5

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

.github/workflows/test.yml

@@ -59,7 +59,7 @@ jobs:
         name: Set up Go
         uses: actions/setup-go@v2
         with:
-          go-version: 1.18.4
+          go-version: 1.18.5
       -
         name: Test
         run: |