Make more atomic tests for lox_context
As @cohosh mentioned in !129 (merged), some of the tests in lox-distributor/src/lox_context
test a lot of things all at once. This might be useful to test that the system does what we expect, but should also include more atomic unit tests that check individual cases. For example we could have a test for each of the following:
- require a replacement of a spare bridge
- require a replacement that requires dissolving a bucket of spares
- require a replacement but we don't have any unallocated bridges
- try to replace an unallocated bridge