fix(build): Fix environment variable check in main function

Add check for the CARGO_ENCODED_RUSTFLAGS environment variable to ensure the correctness of the relocation-model=dynamic-no-pic option. Configure the following in .cargo/config.toml: ```toml [target.x86_64-unknown-linux-gnu] rustflags = ["-C", "relocation-model=dynamic-no-pic"] ``` rustc uses the CARGO_ENCODED_RUSTFLAGS environment variable. See: [https://doc.rust-lang.org/cargo/reference/environment-variables.html](https://doc.rust-lang.org/cargo/reference/environment-variables.html)