Fix typo in variable name and make check more accurate

Signed-off-by: Joas Schilling <coding@schilljs.com>

diff --git a/build/image-optimization.sh b/build/image-optimization.sh
index 81866a0fee44518fe5a7a4ac5adf4dfbc55fa2f1..6d494b8ddb7def71264dcc919f5935ece5bde3c9 100755 (executable)
--- a/build/image-optimization.sh
+++ b/build/image-optimization.sh
@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 
 CHECK_DIR='../'
-if ! [ "$SERVER_VERSION" ]; then
+if [[ -d "$1" ]]; then
        CHECK_DIR=$1
 fi