[chore] rebuild protos with setted env

[MCJOHN974]

Description

Closes: No issue.

Changes

Now our build will rebuild protobufs with REBUILD_PROTOS env setted.

Testing Information

I just tried it few times on my machine

Checklist:

• I have performed a self-review of my code
• My changes generate no new warnings
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[cylewitruk]

Not sure with others think, but one suggestion could be to add a bin to Cargo.toml for the build script specifically. I haven't tried this, but I've seen it somewhere:

[[bin]]
name = "signer-build-script"
path = "build.rs"

And update the Makefile with a new rule:

# ##############################################################################
# MAIN TARGETS
# ##############################################################################
...
contracts:
	pnpm --prefix contracts run build

+protos:
+       REBUILD_PROTOS=true cargo $(CARGO_FLAGS) run --bin signer-build-script
+.PHONY: install build test test-build lint format contracts clean protos
-.PHONY: install build test test-build lint format contracts clean
...

[MCJOHN974]

Yeas, this sounds better, thanks @cylewitruk