doc: fix the Git clone instructions

Signed-off-by: Andreas Reichel <andreas@manticore-projects.com>
Signed-off-by: manticore-projects <andreas@manticore-projects.com>

Author: manticore-projects

src/site/sphinx/usage.rst

@@ -25,15 +25,15 @@ You will need to have ``JDK 8`` or ``JDK 11`` installed. Please note that JSQLPa
   .. code-block:: shell
 
     git clone --depth 1 https://github.com/JSQLParser/JSqlParser.git
-    cd JSqlParser/
+    cd JSqlParser
     mvn install
 
 .. tab:: Gradle
 
   .. code-block:: shell
 
     git clone --depth 1 https://github.com/JSQLParser/JSqlParser.git
-    cd JSqlParser/
+    cd JSqlParser
     gradle publishToMavenLocal