gui: Use MINUS (U+2212) instead of HYPHEN-MINUS (U+002D) #15034

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<!--- What behavior did you expect? -->

MINUS (U+2212) is used if money is removed from wallet.

<!--- What was the actual behavior (provide screenshots if the issue is GUI-related)? -->

HYPHEN-MINUS (U+002D) is used if money is removed from wallet.

<!--- How reliably can you reproduce the issue, what are the steps to do so? -->

1. Run bitcoin-qt -regtest
2. Mine some blocks
3. Send some coins

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0.17.0.1, website

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GNU/Linux, x86_64, HDD

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What's the problem? There's no issue that I can see. Changing this seems pointless and just makes stuff gratuitously incompatible with real world keyboards and copy/paste to other software??

@luke-jr, Bitcoin Core is already using some Unicode characters.

So? That's not a reason to use U+2212 instead of U+002D (which is also a Unicode character, FWIW).