[Request] Improve [Request] and [Bug] templates

[Darxo]

Is your feature request related to a problem? Please describe.
The current [Request] and [Bug] templates suggest bold formatting as a default for highlighting the different major sections.
However when a section grows larger, the author will want to split it into subsections. But with the section itself already only using a simple bold for formatting, he is out of options to do so.

Describe the solution you'd like
Change the template to use any of the three section format #, ## or ### instead of bold.
I tend towards ### as I find the others too big.

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