Handle Repeat key events when using the crossterm backend

[cxreiff]

Problem

In certain terminal environments where holding a key sends multiple Press events, tui-input's key event handler works as expected. However in terminal environments that properly support Repeat key events, tui-input will toss out those events because of the enum equality check on src/backend/crossterm.rs:22. For example, pressing and holding a character will only type a single, initial character.

Solution

Adding KeyEventKind::Repeat to the match arm condition means that Repeat events will be handled correctly, while Release events will continue to be ignored.

Testing

Added a unit test, and tested the examples.

Note

Most of the green/red in the diff below is an indent from the formatter, the significant change is just line 22:

}) if *kind == KeyEventKind::Press || *kind == KeyEventKind::Repeat => {

[sayanarijit]

Thank you...