Update to Go 1.18 and replace fnv-1a with xxhash (#158)

* Update modules and go 1.18

* Use xxhash instead of fnv-1a

* Update go version in dockerfile and github workflow

.github/workflows/go.yml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         os: [ ubuntu-latest, windows-latest, macos-latest ]
-        goversion: [ 1.17 ]
+        goversion: [ 1.18 ]
     
     runs-on: ${{ matrix.os }}
     steps: