Remove Ubuntu CUDA12 GPU workflow; bump submodule

Delete legacy .github/workflows/release_ubuntu_gpu_cuda12.yml and apply minor whitespace cleanups across multiple GitHub Actions workflows (generate_deploy_documentation, release_macos, release_ubuntu, release_ubuntu_gpu, release_windows, release_windows_gpu). Update src/radarsimcpp submodule to commit 7a758f3. These changes remove the obsolete CUDA12 GPU workflow and tidy up CI files.

Author: zpeng

.github/workflows/generate_deploy_documentation.yml

@@ -59,7 +59,7 @@ jobs:
           python -m pip install --upgrade pip
           pip install -r requirements-dev.txt
         shell: bash
-      
+
       - name: Install mbedTLS
         run: |
           sudo apt-get update

.github/workflows/release_macos.yml

@@ -169,7 +169,7 @@ jobs:
         run: |
           python -m pip install --upgrade pip wheel setuptools
           pip install -r requirements-dev.txt
-      
+
       - name: Install mbedTLS
         run: |
           brew install mbedtls

.github/workflows/release_ubuntu.yml

@@ -159,7 +159,7 @@ jobs:
         run: |
           python -m pip install --upgrade pip wheel setuptools
           pip install -r requirements-dev.txt
-      
+
       - name: Install mbedTLS
         run: |
           sudo apt-get update

.github/workflows/release_ubuntu_gpu.yml

@@ -177,7 +177,7 @@ jobs:
         run: |
           python -m pip install --upgrade pip wheel setuptools
           pip install -r requirements-dev.txt
-      
+
       - name: Install mbedTLS
         run: |
           sudo apt-get update