Bug 1433163 - Increase android reftest test chunks; r=jmaher

taskcluster/ci/test/reftest.yml

@@ -98,8 +98,8 @@ reftest:
     virtualization: virtual-with-gpu
     chunks:
         by-test-platform:
-            android-4.3-arm7-api-16/debug: 48
-            android.*: 24
+            android-4.3-arm7-api-16/debug: 56
+            android.*: 28
             macosx64.*/opt: 1
             macosx64.*/debug: 2
             windows10-64.*/opt: 1