Revert "Update .travis.yml"

This reverts commit 534af1c.

Fixes Travis release issue:
```
unexpected token `(', conditional binary operator expected
expected `)'
syntax error near `(env(v'
``  if [[ (env(version)=10) && ("$TRAVIS_TAG" != "") ]]; then
```

Author: Sam Harrison

.travis.yml

@@ -19,7 +19,7 @@ deploy:
     skip_cleanup: true
     on:
       tags: true
-      condition: env(version)=10
+      condition: $version=10
 
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