Test output never de-nests

[rofrankel]

For example, at time of writing, https://github.com/Kampfkarren/protoc-gen-luau/pull/15 has the unit test output shown below. Each of Value, Timestamp, Duration, and "wrapper for" are same-level describes.

   Compiling protoc-gen-luau v0.1.0 (C:\Users\rfrankel\work\protoc-luau\protoc-gen-luau)
    Finished release [optimized] target(s) in 4.96s
     Running unittests src\main.rs (target\release\deps\protoc_gen_luau-bc208dfc475bbe61.exe)

running 1 test
json deserializing
        ✅ should deserialize and reserialize primitives
JSON round-trips should work for
        Value
                ✅ with null value
                ✅ with number value
                ✅ with string value
                ✅ with boolean value
                ✅ with struct value
                ✅ with list value
                Timestamp
                        ✅ with seconds
                        ✅ with seconds and nanos
                        Duration
                                ✅ with seconds
                                ✅ with seconds and nanos
                                wrapper for
                                        ✅ bool
                                        ✅ int32
                                        ✅ int64
                                        ✅ uint32
                                        ✅ uint64
                                        ✅ float
                                        ✅ double
                                        ✅ string
                                        ✅ bytes
test luau_tests::basic ... ok

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.47s

[Kampfkarren]

Fixed by #26