Porechop bar charts result in error when no adapters found by tool

[jfy133]

The recently added porechop module was only tested on a log file from a file that did in fact have adapters. We've just learnt that when there are no adapters, Porechop does not report the log file sections used in the current MultiQC module (resulting in a 'no data found' error in MultiQC).

The MultiQC module should be updated to either skip the add_section call when the corresponding values are not found, or could have a custom HTML div + .alert that explains why (suggested by @ewels )

I will assign this to @sofstam and myself

[jfy133]

Porechop_NoAdaptersFound.log

test data to go on the repo when we get to this :)

[ewels]

@jfy133 - done ✅ 😊