Correct unit abbreviation in README.md

Corrected instances of "Gb" to "GB" in the README.md file. The
lowercase "b" could be misinterpreted as gigabit.

README.md

@@ -29,12 +29,12 @@ To use the workflows, you need to have the following models installed in ComfyUI
 Place them in the corresponding directories as specified below.
 
  * \<YOUR_COMFYUI_DIR\> __/ models / checkpoints :__
- * [pixart_sigma-FP16.safetensors](https://huggingface.co/martin-rizzo/AbominableWorkflows/tree/main) (1.2Gb)
- * [photon_refiner-FP16.safetensors](https://huggingface.co/martin-rizzo/AbominableWorkflows/tree/main) (2.1Gb)
+ * [pixart_sigma-FP16.safetensors](https://huggingface.co/martin-rizzo/AbominableWorkflows/tree/main) (1.2GB)
+ * [photon_refiner-FP16.safetensors](https://huggingface.co/martin-rizzo/AbominableWorkflows/tree/main) (2.1GB)
  * \<YOUR_COMFYUI_DIR\> __/ models / clip :__
- * [t5_xxl_encoder-FP8.safetensors](https://huggingface.co/martin-rizzo/AbominableWorkflows/tree/main) (4.9Gb)
+ * [t5_xxl_encoder-FP8.safetensors](https://huggingface.co/martin-rizzo/AbominableWorkflows/tree/main) (4.9GB)
  * \<YOUR_COMFYUI_DIR\> __/ models / vae :__
- * [pixart_vae.safetensors](https://huggingface.co/martin-rizzo/AbominableWorkflows/tree/main) (0.1Gb)
+ * [pixart_vae.safetensors](https://huggingface.co/martin-rizzo/AbominableWorkflows/tree/main) (0.1GB)
 
 ## Required Nodes