Reduce implicit cast compilation warnings

[jeroenbakker-atmind]

Description

Replacing implicit casts with static casts.
This PR doesn't do any functional or code flow changes, only making casts explicit.

/Users/jeroen/vulkan-git/Vulkan-Samples/samples/extensions/dynamic_line_rasterization/dynamic_line_rasterization.cpp:117:53: warning: implicit conversion loses integer precision: 'unsigned long' to 'uint32_t' (aka 'unsigned int') [-Wshorten-64-to-32]
        uint32_t vertex_buffer_size      = vertices.size() * sizeof(glm::vec3);
                 ~~~~~~~~~~~~~~~~~~        ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
/Users/jeroen/vulkan-git/Vulkan-Samples/samples/extensions/dynamic_line_rasterization/dynamic_line_rasterization.cpp:118:57: warning: implicit conversion loses integer precision: 'unsigned long' to 'uint32_t' (aka 'unsigned int') [-Wshorten-64-to-32]
        uint32_t cube_index_buffer_size  = cube_indices.size() * sizeof(uint32_t);
                 ~~~~~~~~~~~~~~~~~~~~~~    ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
/Users/jeroen/vulkan-git/Vulkan-Samples/samples/extensions/dynamic_line_rasterization/dynamic_line_rasterization.cpp:119:58: warning: implicit conversion loses integer precision: 'unsigned long' to 'uint32_t' (aka 'unsigned int') [-Wshorten-64-to-32]
        uint32_t edges_index_buffer_size = edges_indices.size() * sizeof(uint32_t);
                 ~~~~~~~~~~~~~~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
3 warnings generated.

General Checklist:

Please ensure the following points are checked:

• My code follows the coding style
• I have reviewed file licenses
• I have commented any added functions (in line with Doxygen)
• I have commented any code that could be hard to understand
• My changes do not add any new compiler warnings
• My changes do not add any new validation layer errors or warnings
• I have used existing framework/helper functions where possible
• My changes do not add any regressions
• I have tested every sample to ensure everything runs correctly
• This PR describes the scope and expected impact of the changes I am making

Note: The Samples CI runs a number of checks including:

• I have updated the header Copyright to reflect the current year (CI build will fail if Copyright is out of date)
• My changes build on Windows, Linux, macOS and Android. Otherwise I have documented any exceptions

[CLAassistant]

All committers have signed the CLA.

[jeroenbakker-atmind]

I had to force push as the CLA didn't like using not default email address in commit.
Note this is still a draft as there are other similar warnings in other areas I wanted to look into.