Add support for the crypto refresh in v2 (#265)

This commit adds support for the OpenPGP crypto-refresh.
- Updates go-crypto dependency to v1.1.0-alpha.1
- Adapts the session key logic to handle PKESK/SKESK v6 packets without an algorithm attached
- Updates the min go version to 1.17 as requires by  go-crypto v1.1.0-alpha.1
- Update the cricl dependency to 1.3.7 matching go-crypto
Not supported:
- crypto-refresh intended recipients
- v6 key generation

.github/workflows/go.yml

@@ -23,16 +23,16 @@ jobs:
         run: go test -v -race ./...
 
   test-old:
-    name: Test with 1.15
+    name: Test with 1.17
     runs-on: ubuntu-latest
     steps:
     - name: Check out repo
       uses: actions/checkout@v3
 
-    - name: Set up Go 1.15
+    - name: Set up Go 1.17
       uses: actions/setup-go@v3
       with:
-        go-version: 1.15
+        go-version: 1.17
 
     - name: Test
       run: go test -v -race ./...