bug: fails to build on termux

[martindmtrv]

https://github.com/clearloop/leetcode-cli/blob/main/src/plugins/chrome.rs#L150

The chrome plugin conditionally compiles functions based on target os

When building on termux it's not considered a Linux host

~ $ rustc -vV | grep host
host: aarch64-linux-android

So these functions are missing

   Compiling leetcode-cli v0.5.3
error[E0425]: cannot find function `cookie_db_path` in this scope
  --> /data/data/com.termux/files/home/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/leetcode-cli-0.5.3/src/plugins/chrome.rs:64:14
   |
64 | ... = cookie_db_path().ok_or(Error::ChromeNotLog...
   |       ^^^^^^^^^^^^^^ not found in this scope

error[E0425]: cannot find function `encryption_key` in this scope
  --> /data/data/com.termux/files/home/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/leetcode-cli-0.5.3/src/plugins/chrome.rs:79:15
   |
79 |     let key = encryption_key()?;
   |               ^^^^^^^^^^^^^^ not found in this scope

For more information about this error, try `rustc --explain E0425`.
error: could not compile `leetcode-cli` (lib) due to 2 previous errors
warning: build failed, waiting for other jobs to finish...
error: failed to compile `leetcode-cli v0.5.3`, intermediate artifacts can be found at `/data/data/com.termux/files/usr/tmp/cargo-installPhiuoL`.
To reuse those artifacts with a future compilation, set the environment variable `CARGO_BUILD_BUILD_DIR` to that path.

I think it's fine for these to just be defined as stubs on non supported host. The chrome plugin won't work in termux anyway!