Fixed header levels

machine-and-deep-learning/vllm/README.md

@@ -8,7 +8,7 @@ Python examples contained in this directory have been taken from https://github.
 
 ## 1. Running vLLM
 
-## 1.1. Running vLLM using Apptainer (recommended)
+### 1.1. Running vLLM using Apptainer (recommended)
 
 A vLLM container will be centrally provided on our HPC system **very soon**. However, for now lets assume we created one with the following command:
 ```bash
@@ -28,7 +28,7 @@ zsh submit_job_container.sh
 sbatch submit_job_container.sh
 ```
 
-## 1.2. Running vLLM in a custom Python environment
+### 1.2. Running vLLM in a custom Python environment
 
 This option assumes that you already have a working custom virtual environment, e.g., through the following instructions:
 ```bash