fix(ci): 将删除MFA自带MaaFw的步骤后置 (#30)

## 由 Sourcery 提供的总结

CI：
- 在安装工作流程中，将移除 MFA 内置运行时的步骤移动到下载并解压 MFAAvalonia 之后再执行。

<details>
<summary>Original summary in English</summary>

## Summary by Sourcery

CI:
- Move the MFA built-in runtime removal step to after the MFAAvalonia
download and extraction step in the install workflow.

</details>

Author: Natsuu

.github/workflows/install.yml

@@ -83,12 +83,6 @@ jobs:
           out-file-path: "deps"
           extract: true
 
-      - name: Remove built-in runtime in MFA
-        if: matrix.os != 'android'
-        shell: bash
-        run: |
-          rm -rf MFA/runtimes
-
       - name: Download MFAAvalonia
         if: matrix.os != 'android'
         id: download_mfa
@@ -108,6 +102,12 @@ jobs:
           rm -f "${ARCHIVE_FILE_PATH}"
           echo "Archive cleanup command executed for MFAAvalonia."
 
+      - name: Remove built-in runtime in MFA
+        if: matrix.os != 'android'
+        shell: bash
+        run: |
+          rm -rf MFA/runtimes
+      
       - name: Install
         shell: bash
         run: |