Merge pull request #459 from drakkan/go117

CI: add Go 1.17 and remove 1.15
diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index 47cc5f1..2e61a75 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -12,10 +12,10 @@
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest]
-        go: [1.16, 1.15]
+        go: [1.17, 1.16]
         exclude:
           - os: macos-latest
-            go: 1.15
+            go: 1.16
 
     steps:
       - uses: actions/checkout@v2