* fix(input-number): fix increase/decrease button not work
- fix increase/decrease not work when modelValue not in [min, max]
* test(input-number): add a test case which check increase/decrease button
* fix(input-number): fix input-number behavior error
- After input-number is cleared, the focus is lost and the value of v-model is not changed when the value of Min is changed
* test(input-number): add input-number test case
* docs(input-number): update modelValue's description
