Simple value binding adds input before value

[davidenke]

Mutating an input field without ngControl adds the new value before the existing. Reproducable in the demo on the number input field.

[connollykeyjoint]

This issue appears to be related to a number type input. If you change the input to a regular text input the issue disappears.

Although there is still an error in the console: ERROR TypeError: Cannot read property 'value' of undefined

Referring to this line: https://github.com/ngx-material-keyboard/core/blob/b9e750cd98ef77678239bd5bdb3ffd67305cc5b3/src/core/src/components/keyboard-key/keyboard-key.component.ts#L275