Fixup: variable key

Author: gnzlbg

azure-pipelines.yml

@@ -67,7 +67,7 @@ jobs:
           TARGET: x86_64-unknown-linux-gnux32
         x86_64-unknown-linux-musl:
           TARGET: x86_64-unknown-linux-musl
-      variables:
+      variable:
         TOOLCHAIN: nightly
 
   - job: Docker-OSX
@@ -89,7 +89,7 @@ jobs:
           TARGET: i686-apple-darwin
         x86_64-apple-darwin:
           TARGET: x86_64-apple-darwin
-      variables:
+      variable:
         TOOLCHAIN: nightly