fix: add whitespace after tapping the suggestion text

[hanwencheng]

close #529 .

Now after tapping the suggestion text, the trailing space will be automatically added.

And for a 24 words recovery phrase, it will not add the whitespace to the end.

But for a 12, 15, 18, or 21 words (They should all be possible to be recovered), the trailing whitespace is still added, but after tapping the "Recover Identity" button and input PIN, it will automatically be trimmed.

Test cases:

1. tapping any suggestion word, a whitespace should follow.
2. move the cursor to middle, and add another suggestion word, no extra trailing whitespace in the end should be added.
3. After input bip39 mnemonic phrase, the box border should not be red though there is a trailing whitespace.
4. after input bip39 mnemonic phrase and recovered the identity, the recover phrase should not include any trailing whitespace, they should be removed during recovery process.
5. After input 24 bip39 words, there should be no more traling whitespaces added.