Update .travis.yml

Fixing the jobs in travis

Author: sambitdash

.travis.yml

@@ -10,6 +10,10 @@ os:
   - linux
   - osx
   - windows
+jobs:
+  allow_failures:
+    - julia: nightly
+    - julia: 1.6
 
 notifications:
   email: false
@@ -18,9 +22,6 @@ after_success:
   - julia -e 'import PDFIO; cd(joinpath(dirname(pathof(PDFIO)), "..")); using Pkg; Pkg.add("Coverage"); using Coverage; Codecov.submit(Codecov.process_folder())'
 
 jobs:
-  allow_failures:
-    - julia: nightly
-    - julia: 1.6
   include:
     - stage: "Documentation"
       julia: 1.5