dialer-button: Improve letters only button style

Increase the size of the secondary label if the primary label is empty.
This would improve the way '*' and '#' are displayed.
1 job for wip/sadiq/dialer-button in 2 minutes and 11 seconds (queued for 19 minutes and 9 seconds)
latest
Status Job ID Name Coverage
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passed #2079
librem5
build-debian

00:02:11