.gitignore: Add .env.

Change-Id: Iae8fe8ef9f6aa5ff077484f35cb06b5695656b8e
diff --git a/.gitignore b/.gitignore
index f87d829..469f2d4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -55,3 +55,4 @@
 
 # Credentials
 keys.p12
+/.env