tests: add package libcpputest-dev for ubuntu/precise (Travis CI)

.travis.yml

@@ -16,8 +16,7 @@ before_script:
     - echo 'APT::Install-Recommends "false";' | sudo tee -a /etc/apt/apt.conf
     - sudo apt-get update -qq
     - sudo apt-get -y install devscripts equivs python-pip libenchant-dev autopoint asciidoc source-highlight xsltproc docbook-xsl docbook-xml cmake pkg-config libncursesw5-dev gem2deb libperl-dev python-dev python3-dev libaspell-dev liblua5.1-0-dev tcl8.5-dev guile-2.0-dev libv8-dev libcurl4-gnutls-dev libgcrypt11-dev libgnutls-dev zlib1g-dev curl
-    - curl -OL http://weechat.org/files/tests/ubuntu/precise/amd64/libcpputest-dev_3.4-3_amd64.deb
-    - sudo dpkg -i libcpputest-dev_3.4-3_amd64.deb
+    - sudo dpkg -i ./tests/ubuntu/precise/libcpputest-dev_3.4-3_amd64.deb
     - sudo pip install msgcheck pylint
 
 script: