Pattern: Use of &, ;, &> or similar after a here-document
Issue: -
You are using &, ;, &> or similar after a here-document. This is not allowed. This should instead be part of the line that initiated the here-document, i.e. the one with the <<.
If it helps, look at << "END" as if it was < file, and make sure the resulting command is valid. This is what the shell does. You can then append here-document data after the command.
Example of incorrect code:
sudo bash -s << "END"
cmd1
cmd2
END &
Example of correct code:
sudo bash -s << "END" &
cmd1
cmd2
END