simplify if-clause

Author: ocefpaf

.travis.yml

@@ -29,11 +29,12 @@ script:
   - |
     set -e
     if [[ -z "$TRAVIS_TAG" ]]; then
-      python -m doctr deploy --build-tags --key-path github_deploy_key_oceanhackweek_oceanhackweek_github_io.enc --built-docs _site/ dev
+      DEPLOY_DIR=dev
     else
-      python -m doctr deploy --build-tags --key-path github_deploy_key_oceanhackweek_oceanhackweek_github_io.enc --built-docs _site/ "version-$TRAVIS_TAG"
-      python -m doctr deploy --build-tags --key-path github_deploy_key_oceanhackweek_oceanhackweek_github_io.enc --built-docs _site/ .
+      DEPLOY_DIR="version-$TRAVIS_TAG"
     fi
+    python -m doctr deploy --build-tags --key-path github_deploy_key_oceanhackweek_oceanhackweek_github_io.enc --built-docs _site/ $DEPLOY_DIR
+    python -m doctr deploy --build-tags --key-path github_deploy_key_oceanhackweek_oceanhackweek_github_io.enc --built-docs _site/ .
 
 doctr:
   require-master: true