Remove sudo key and add a name to sami job on TravisCI config

Signed-off-by: William Desportes <williamdes@wdes.fr>

.travis.yml

@@ -22,6 +22,7 @@ matrix:
     - php: nightly
   include:
     - php: 7.2
+      name: "Build documentation"
       env:
         - DOCS=yes
         - REQUIRE="sami/sami:^4.0"
@@ -32,8 +33,6 @@ matrix:
     - dist: precise
       php: 5.3
 
-sudo: false
-
 install:
   - if [ -n "$REQUIRE" ] ; then composer require "$REQUIRE" ; fi
   - composer install