Add a linefeed between end token and terminating ')'.

Problematic code:

var=$(fmt -s "$COLUMNS" << "eof"
This is a bunch of text
eof)

Correct code:

var=$(fmt -s "$COLUMNS" << "eof"
This is a bunch of text
eof
)

Rationale:

When embedding a here document in $(..) or (..), there needs to be a linefeed (newline) between the here doc token and the closing ). Please insert one.

Failing to do so may cause warnings like this:

bash: warning: here-document at line 15 delimited by end-of-file (wanted `eof')`
dash: 5: Syntax error: end of file unexpected (expecting ")")

Exceptions:

This error may be incorrectly emitted for ksh, where this is allowed. In this case, please either write it in a standard way or ignore this warning.