add OTP 26 for windows ci (#269)

Author: cocoa-xu

.github/workflows/precompile.yml

@@ -20,7 +20,7 @@ jobs:
       matrix:
         os: ["ubuntu-20.04", "windows-2019", "macos-11"]
         elixir: ["1.14"]
-        otp: ["25", "23"]
+        otp: ["26", "25", "23"]
         exclude:
           - os: "windows-2019"
             otp: "23"