Filter out Sanger reads that consist of gaps ('-') or unknown characters ('N') only

When the attached "pFB7-CDK5RAP2_P1713799_043.ab1" read is mapped to the to reference, the BLAST+ step in the Sanger reads mapping task fails with the following error:

[ERROR][15:49] Task {Map Sanger reads to reference} finished with error: Subtask {Align reads with BLAST & SW task} is failed: Subtask {Align one read with BLAST & SW task} is failed: Subtask {Run NCBI Blast+ task} is failed: Error: NCBI C++ Exception: 

The error happens when a read consists of gaps or N characters only.

Check a read in advance before using BLAST+. If a read consists of gaps/N's, consider that it's similarity with the reference is "0". Put the read into the "Filtered by low similarity" group in the Sanger reads mapping task report.