chore: remove appveyor allow node12 failure (#17)

diff --git a/appveyor.yml b/appveyor.yml
index 6fd0acd..4752c73 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -8,10 +8,6 @@
   - nodejs_version: 10
   - nodejs_version: 12
 
-matrix:
-  allow_failures:
-    - nodejs_version: 12
-
 install:
   - ps: Install-Product node $env:nodejs_version
   - npm install