SC2039 "In POSIX sh, echo flags are undefined." triggered for /bin/echo

[ribx]

For bugs

• Rule Id: SC2039
• My shellcheck version: integrated in hadolint 1.16.3
• The rule's wiki page does not already cover this (e.g. https://shellcheck.net/wiki/SC2086)
• I tried on shellcheck.net and verified that this is still a problem on the latest commit

Here's a snippet or screenshot that shows the problem:

#!/bin/sh
/bin/echo -e "test\ntest"

Here's what shellcheck currently says:

Line 2:
/bin/echo -e "test\ntest"
          ^-- SC2039: In POSIX sh, echo flags are undefined.

Here's what I wanted or expected to see:

When I use /bin/echo it should not complain about "echo in POSIX sh", as I am using the binary and not the shell internal function.