feat: add ${GLOBAL_REGISTRY} for change docker image

src/gpustack/README.md

@@ -67,7 +67,7 @@ To use AMD GPUs with ROCm support:
 1. Use the ROCm-specific image in `docker-compose.yaml`:
 
    ```yaml
-   image: gpustack/gpustack:${GPUSTACK_VERSION:-v0.7.1}-rocm
+   image: ${GLOBAL_REGISTRY:-}gpustack/gpustack:${GPUSTACK_VERSION:-v0.7.1}-rocm
    ```
 
 2. Change the device driver to `amdgpu`:

src/gpustack/README.zh.md

@@ -67,7 +67,7 @@ deploy:
 1. 在 `docker-compose.yaml` 中使用 ROCm 特定镜像：
 
    ```yaml
-   image: gpustack/gpustack:${GPUSTACK_VERSION:-v0.7.1}-rocm
+   image: ${GLOBAL_REGISTRY:-}gpustack/gpustack:${GPUSTACK_VERSION:-v0.7.1}-rocm
    ```
 
 2. 将设备驱动更改为 `amdgpu`：

src/gpustack/docker-compose.yaml

@@ -9,7 +9,7 @@ x-defaults: &defaults
 services:
   gpustack:
     <<: *defaults
-    image: gpustack/gpustack:${GPUSTACK_VERSION:-v0.7.1}
+    image: ${GLOBAL_REGISTRY:-}gpustack/gpustack:${GPUSTACK_VERSION:-v0.7.1}
     ports:
       - "${GPUSTACK_PORT_OVERRIDE:-80}:80"
     volumes: