Update README.md

Author: Oliver Weiler

README.md

@@ -54,7 +54,7 @@ implementation("io.github.helpermethod:zip-forge:0.1.0")
 The following code snippet calls `createZipFile` to create the ZIP file at the given location.
 It uses the `file` and `directory` methods to create files and directories within the context of the ZIP file.
 
-:warning: `file` and `directory` should never be used outside of `createZipFile`'s or `directory`'s context.
+:bulb: `file` and `directory` should never be used outside of `createZipFile`'s or `directory`'s context.
 
 ```java
 import java.nio.charset.StandardCharsets;