Update sed command for compatibility with MacOS

Adapted the sed command in the prepare-dotenv.sh script to ensure compatibility with both MacOS and Linux. Previously, the script only worked on Linux systems, but now it accounts for differences in the sed command on Unix-based systems.

scripts/prepare-dotenv.sh

@@ -13,10 +13,19 @@ else
 
   for environment in $environments
   do
-      # Create a copy of .env.sample for each environment
-      cp .env.sample .env.$environment
+    # Create a copy of .env.sample for each environment
+    cp .env.sample .env.$environment
 
-      # Replace ENV= with ENV=<environment> in each file
-      sed -i "s/^ENV=.*$/ENV=$environment/g" .env.$environment
+    # Replace ENV= with ENV=<environment> in each file
+    # The command differs depending on the Unix-based system (Linux/BSD) or Mac, due to differences in the sed command
+    # - On GNU sed (default on Linux), no space is used between -i and '' (or ""): sed -i'' 's/foo/bar/g'.
+    # - On BSD sed (default on MacOS), a space is required between -i and '' (or ""): sed -i '' 's/foo/bar/g'.
+    if [ "$(uname)" = "Darwin" ]; then
+      # Mac OS X
+      sed -i '' -e "s/^ENV=.*$/ENV=$environment/g" .env.$environment
+    else
+      # Linux and others
+      sed -i'' -e "s/^ENV=.*$/ENV=$environment/g" .env.$environment
+    fi
   done
 fi