Update L4 guide (#268)

* Expose port 22 to enable SSH

* Add boot drive note and remove repo step

source/guides/l4-gcp.md

@@ -12,7 +12,8 @@ To create a VM instance with an L4 GPU to run RAPIDS:
 1. Select **Create Instance**.
 1. Under the **Machine configuration** section, select **GPUs** and then select `NVIDIA L4` in the **GPU type** dropdown.
 1. Under the **Boot Disk** section, click **CHANGE** and select `Deep Learning on Linux` in the **Operating System** dropdown.
-1. Once you have customized other attributes of the instance, click **CREATE**
+1. It is also recommended to increase the default boot disk size to something like `100GB`.
+1. Once you have customized other attributes of the instance, click **CREATE**.
 
 ### Allow network access
 
@@ -25,7 +26,7 @@ To access Jupyter and Dask we will need to set up some firewall rules to open up
 3. Give the rule a name like `rapids` and ensure the network matches the one you selected for the VM.
 4. Add a tag like `rapids` which we will use to assign the rule to our VM.
 5. Set your source IP range. We recommend you restrict this to your own IP address or your corporate network rather than `0.0.0.0/0` which will allow anyone to access your VM.
-6. Under **Protocols and ports** allow TCP connections on ports `8786,8787,8888`.
+6. Under **Protocols and ports** allow TCP connections on ports `22,8786,8787,8888`.
 
 #### Assign it to the VM
 
@@ -55,11 +56,6 @@ $ sudo sh cuda_12.1.1_530.30.02_linux.run
 1. [Install NVIDIA Container Toolkit](https://docs.nvidia.com/datacenter/cloud-native/container-toolkit/install-guide.html#setting-up-nvidia-container-toolkit) with the following commands.
 
 ```bash
-$ distribution=$(. /etc/os-release;echo $ID$VERSION_ID) \
-      && curl -fsSL https://nvidia.github.io/libnvidia-container/gpgkey | sudo gpg --dearmor -o /usr/share/keyrings/nvidia-container-toolkit-keyring.gpg \
-      && curl -s -L https://nvidia.github.io/libnvidia-container/$distribution/libnvidia-container.list | \
-            sed 's#deb https://#deb [signed-by=/usr/share/keyrings/nvidia-container-toolkit-keyring.gpg] https://#g' | \
-            sudo tee /etc/apt/sources.list.d/nvidia-container-toolkit.list
 $ sudo apt-get update
 $ sudo apt-get install -y nvidia-container-toolkit
 $ sudo nvidia-ctk runtime configure --runtime=docker