OnScreenClock v0.7.3

A small update adding an option to show the am/pm suffix when enabling the 12-hour clock.

Here is the changelog since last blog post:

v0.7.3 2023-03-31
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+ added am/pm suffix option

v0.7.2 2022-10-30
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* migrate to billing v4 api

v0.7.1 2022-10-07
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* fix untrusted touch blocking on android 12 and up