Fix clippy issues

[dangeross]

Fixes these clippy issues:

error: operator precedence can trip the unwary
   --> sdk-common/src/invoice.rs:100:8
    |
100 |     Ok((block_num & 0xFFFFFF) << 40 | (tx_num & 0xFFFFFF) << 16 | (tx_out & 0xFFFF))
    |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider parenthesizing your expression: `((block_num & 0xFFFFFF) << 40) | ((tx_num & 0xFFFFFF) << 16)`
    |
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#precedence
    = note: `-D clippy::precedence` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::precedence)]`

error: useless conversion to the same type: `breez_sdk_core::error::ConnectError`
    --> /home/runner/work/breez-sdk-greenlight/breez-sdk-greenlight/libs/target/debug/build/breez_sdk-1e37e56222681eb0/out/breez_sdk.uniffi.rs:4064:11
     |
4064 |         }).map_err(Into::into).map_err(<FfiConverterTypeConnectError as uniffi::FfiConverter>::lower)?;
     |           ^^^^^^^^^^^^^^^^^^^^ help: consider removing
     |
     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_conversion
     = note: `-D clippy::useless-conversion` implied by `-D warnings`
     = help: to override `-D warnings` add `#[allow(clippy::useless_conversion)]`