Fix image formatting glitch in docs/devGuideDB/ajbrowser.xml

Fix image formatting glitch in docs/devGuideDB/ajbrowser.xml

An image which should be in its own paragraph was shown inline with the
text, somewhere to the right in the middle of a text paragraph. I
noticed while visually checking if docs generation still works as
expected after the last few commits, so I quickly fixed it.

Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>