Rust compiler optimizations break Node.js bindings

[adzialocha]

When compiling libp2panda with compiler optimization flags enabled (in Cargo.toml) this error pops up:

uniffi-bindgen-node-js generate ./target/release/libp2panda_ffi.so \
	--out-dir ./nodejs/p2panda_ffi
no UniFFI components were found in the library
make: *** [Makefile:14: ffi-nodejs] Error 1