test: add multi-file hot reloading test

[Wodann]

To Do:

• [x] rebase

[codecov[bot]]

Codecov Report

Merging #522 (9599f51) into main (95a9612) will increase coverage by 0.06%. The diff coverage is 79.41%.

:exclamation: Current head 9599f51 differs from pull request most recent head 9d971af. Consider uploading reports for the commit 9d971af to get more accurate results

@@            Coverage Diff             @@
##             main     #522      +/-   ##
==========================================
+ Coverage   87.16%   87.23%   +0.06%     
==========================================
  Files         274      274              
  Lines       31022    31028       +6     
==========================================
+ Hits        27041    27066      +25     
+ Misses       3981     3962      -19     

Impacted Files	Coverage Δ
crates/mun_memory/src/lib.rs	50.00% <0.00%> (ø)
crates/mun_memory/src/mapping.rs	93.69% <0.00%> (-0.57%)	:arrow_down:
crates/mun_memory/src/type/mod.rs	88.88% <ø> (ø)
crates/mun_runtime/src/lib.rs	75.91% <76.47%> (+1.61%)	:arrow_up:
crates/mun_runtime/src/assembly.rs	93.37% <78.57%> (+4.49%)	:arrow_up:
crates/mun_libloader/src/temp_library.rs	93.33% <83.33%> (-6.67%)	:arrow_down:
crates/mun_libloader/src/lib.rs	97.95% <91.66%> (-2.05%)	:arrow_down:
...rates/mun_codegen/src/code_gen/assembly_builder.rs	100.00% <100.00%> (ø)
crates/mun_codegen/src/code_gen/symbols/mod.rs	99.56% <100.00%> (+<0.01%)	:arrow_up:
crates/mun_test/src/driver.rs	87.60% <100.00%> (ø)

... and 2 files with indirect coverage changes