Go lib with demo binary

[Tong Sun <suntong001@users.sourceforge.net>]

Hi,

When building my package
  https://salsa.debian.org/suntong-guest/golang-github-jaguilar-vt100

with `gbp buildpackage`, I'm getting the following error:

E: golang-github-jaguilar-vt100-dev:
arch-independent-package-contains-binary-or-object usr/bin/demo
E: golang-github-jaguilar-vt100-dev: missing-dependency-on-libc needed
by usr/bin/demo
E: golang-github-jaguilar-vt100-dev: unstripped-binary-or-object usr/bin/demo
W: golang-github-jaguilar-vt100-dev: binary-without-manpage usr/bin/demo

The problem is that this is just a Go library, the usr/bin/demo is
only its demo program. How can I silent the above `gbp` error
reporting?

Moreover, I didn't get the following two `gbp buildpackage` warnings
when I'm building with `debuild`, and check with `lintian -EvIL
+pedantic`:

W: golang-github-jaguilar-vt100-dev: description-synopsis-starts-with-article
W: golang-github-jaguilar-vt100-dev:
extended-description-contains-empty-paragraph

I believe they are valid, but how can I get it myself with `debuild`,
and `lintian`?

Thanks