Update 'inventory' create new version in fluvio test

[sehz]

This should be updated to 0.2. Just updating cargo.toml cause compilation error

[tjtelan]

It appears this crate is being deprecated?
The repo and others related were made readonly https://github.com/dtolnay/inventory

More background:
https://www.reddit.com/r/rust/comments/sjrt8f/dtolnayinventory_got_archived_is_there_an/
rust-lang/rust#47384 (comment)

[morenol]

We should retry with new version

[sehz]

@tjtelan can you look into this?

[tjtelan]

I just tried to swap out 0.1 for 0.3 and it looks like there's an incompatibility w/ the macro implementation using .to_string(). Will need to look into the proc macro.

error[E0015]: cannot call non-const fn `<str as ToString>::to_string` in statics
  --> crates/fluvio-test/src/tests/self_test/mod.rs:46:1
   |
46 | #[fluvio_test()]
   | ^^^^^^^^^^^^^^^^
   |
   = note: calls in statics are limited to constant functions, tuple structs and tuple variants
   = note: this error originates in the attribute macro `fluvio_test` (in Nightly builds, run with -Z macro-backtrace for more info)