The basic foundation of internal module testing starts from the bottom layer and with the block manager, this means creating unit tests. This ticket is to aim to unit test the relevant block_session functions used for the block manager module. This ticket will create unit tests for:

• __wti_block_extent_free
• __wti_block_extent_alloc
• __block_extent_prealloc
• __block_extent_alloc

The definition of done, will be thoroughly testing the pack and unpack functions, with clear test cases working with the goal of increasing code coverage.