Delete another extra space

Author: ptheywood

index.md

@@ -11,7 +11,7 @@ header:
     - label: "Docs"
       url: "https://docs.flamegpu.com"
     - label: "Try on Colab"
-       url: "https://colab.research.google.com/github/FLAMEGPU/FLAMEGPU2-tutorial-python/blob/google-colab/FLAME_GPU_2_python_tutorial.ipynb"
+      url: "https://colab.research.google.com/github/FLAMEGPU/FLAMEGPU2-tutorial-python/blob/google-colab/FLAME_GPU_2_python_tutorial.ipynb"
 excerpt: "The Flexible Large-scale Agent Modelling Environment for the Graphics Processing Unit (GPU)"
 feature_row:
   - image_path: /assets/images/gpu_birds_square.png