doc: avoid ` character inside code block
doc: avoid ` character inside code block

The ` character (also its escaped version \`) was confusing the used
Markdown convertor.

Signed-off-by: Jan Viktorin <3eab6ac54c005c4408f608556a6663b7f2abede7@fit.vutbr.cz>

BeeeOn/server,BeeeOn/server,BeeeOn/server,BeeeOn/server