fix(doc): docs build

Docker instructions were not building correctly.

Signed-off-by: J-Alves <joao.alves@arm.com>
Change-Id: Iba8e53c6043843a80c1fa883185afb57a2e90b91
diff --git a/docs/getting_started/building.rst b/docs/getting_started/building.rst
index e419014..500e5b8 100644
--- a/docs/getting_started/building.rst
+++ b/docs/getting_started/building.rst
@@ -82,7 +82,8 @@
 `./build/docker/build.sh`. You can run commands in the container with
 `./build/run_in_container.sh -i bash`:
 
-.. code :: shell
+.. code:: shell
+
    ./build/docker/build.sh
    ./build/run_in_container.sh -i bash
    make
@@ -90,7 +91,8 @@
 Alternatively, the Makefile will automatically use the Docker container
 if the environment variable `HAFNIUM_HERMETIC_BUILD` is set to `true`:
 
-.. code :: shell
+.. code:: shell
+
    ./build/docker/build.sh
    HAFNIUM_HERMETIC_BUILD=true make