minor #135 Extract wkhtmltopdf file path to env variable (Zales0123)

This PR was merged into the 1.0-dev branch.

Discussion
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It was frustrating 🚀 

Commits
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6ba1ae0 Extract wkhtmltopdf file path to env variable

Author: Zales0123

tests/Application/.env

@@ -21,3 +21,7 @@ DATABASE_URL=mysql://root@127.0.0.1/sylius_refund_plugin_%kernel.environment%?se
 # Delivery is disabled by default via "null://localhost"
 MAILER_URL=smtp://localhost
 ###< symfony/swiftmailer-bundle ###
+
+###> knplabs/knp-snappy-bundle ###
+WKHTMLTOPDF_PATH=%kernel.project_dir%/etc/wkhtmltopdf
+###< knplabs/knp-snappy-bundle ###

tests/Application/config/packages/knp_snappy.yaml

@@ -1,5 +1,5 @@
 knp_snappy:
     pdf:
         enabled: true
-        binary: /usr/local/bin/wkhtmltopdf
+        binary: '%env(resolve:WKHTMLTOPDF_PATH)%'
         options: []