Prepare release v1.9.0 (#68)

Release v1.9.0 with updated dependency and support for `AppendFunc`.
diff --git a/.github/workflows/go.yml b/.github/workflows/go.yml
index 22f771f..6ac89ec 100644
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -13,7 +13,7 @@
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        go: ["1.17.x", "1.18.x", "1.19.x"]
+        go: ["1.18.x", "1.19.x"]
         include:
         - go: 1.19.x
           latest: true
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3ba0527..d2c8aad 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,14 @@
 Releases
 ========
 
+v1.9.0 (2022-12-12)
+===================
+
+-   Add `AppendFunc` that allow passsing functions to similar to
+    `AppendInvoke`.
+
+-   Bump up yaml.v3 dependency to 3.0.1.
+
 v1.8.0 (2022-02-28)
 ===================
 
diff --git a/go.mod b/go.mod
index 60e27b3..6326aa4 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module go.uber.org/multierr
 
-go 1.18
+go 1.19
 
 require (
 	github.com/stretchr/testify v1.7.0