Revert "ImageDecoder: add "image/avif" to support list"

Revert submission 22114263-cherrypick-avif_cts-6vuisjq0md

Reason for revert: b/275081444

Reverted changes: /q/submissionid:22114263-cherrypick-avif_cts-6vuisjq0md

Change-Id: I2cfedc608ae8803f811ae1d99b2f4e057ae3db81
diff --git a/graphics/java/android/graphics/ImageDecoder.java b/graphics/java/android/graphics/ImageDecoder.java
index 60898ef..51f99ec 100644
--- a/graphics/java/android/graphics/ImageDecoder.java
+++ b/graphics/java/android/graphics/ImageDecoder.java
@@ -914,7 +914,6 @@
             case "image/gif":
             case "image/heif":
             case "image/heic":
-            case "image/avif":
             case "image/bmp":
             case "image/x-ico":
             case "image/vnd.wap.wbmp":