Searches for campaigns matching any or all the attributes given as arguments.
If the campaignAttributes argument is omitted findCampaignsBy returns all of the campaigns for the selected channel that are not
in the HIDDEN state.
selectedAttributes is used to limit the information returned for each campaign. If specified, only the named attributes are returned,
otherwise the whole Campaign is returned for each matching campaign. Note that the campaign identifier is always returned, as well as default values for some of the fields (campaign name is set to the empty string, deferred and removeDuplicates are set to
|attributes||CampaignAttributes||Attributes to search by.|
|selectedAttributes||xs:string||A list of campaign attributes to be returned.|
|Campaigns||A group of campaigns.|