Fix test syntax

Author: sfackler

.travis.yml

@@ -3,12 +3,11 @@ cache: cargo
 sudo: required
 rust:
 - nightly
-- beta
 - 1.10.0
 addons:
   postgresql: 9.4
 before_script:
 - "./.travis/setup.sh"
 script:
 - cargo test
-- cargo test --features (cargo read-manifest | jq -r '.features|keys|map(select(. != "with-security-framework"))|join(" ")')
+- cargo test --features $(cargo read-manifest | jq -r '.features|keys|map(select(. != "with-security-framework"))|join(" ")')