fix(fmt): multiline single param only if func definition is multiline for all_params

[ChiTimesChi]

Motivation

Follow-up for #9176. Spec is defined in #9176 (comment)

Solution

• When all_params is selected, multiline the single parameter only when the full function definition takes more than a single line (i.e. multilined).

[ChiTimesChi]

@grandizzy please let me know if styling needs to be adjusted here. Seems to do the job functionality-wise.

[grandizzy]

@grandizzy please let me know if styling needs to be adjusted here. Seems to do the job functionality-wise.

hey @ChiTimesChi please check https://github.com/foundry-rs/foundry/blob/master/CONTRIBUTING.md#resolving-an-issue for formatting, also to run only fmt tests run cargo test from crates/fmt

[ChiTimesChi]

@grandizzy cargo test is all green for me. cargo +nightly fmt -- --check also passes, as well other commands from here:

foundry/CONTRIBUTING.md

Lines 85 to 90 in b74e467

	```sh
	cargo check --all
	cargo test --all --all-features
	cargo +nightly fmt -- --check
	cargo +nightly clippy --all --all-targets --all-features -- -D warnings
	```

I rebased the branch on top of the latest master, so this should be good for the review. Please let me know if I missed anything.