chore(zkstack_cli): build sys contract with --frozen-lockfile (#3138)

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zkstack_cli/crates/common/src/contracts.rs

@@ -26,7 +26,8 @@ pub fn build_l2_contracts(shell: Shell, link_to_code: PathBuf) -> anyhow::Result
 
 pub fn build_system_contracts(shell: Shell, link_to_code: PathBuf) -> anyhow::Result<()> {
     let _dir_guard = shell.push_dir(link_to_code.join("contracts/system-contracts"));
-    Cmd::new(cmd!(shell, "yarn install")).run()?;
+    // Do not update era-contract's lockfile to avoid dirty submodule
+    Cmd::new(cmd!(shell, "yarn install --frozen-lockfile")).run()?;
     Cmd::new(cmd!(shell, "yarn preprocess:system-contracts")).run()?;
     Cmd::new(cmd!(
         shell,