Nope.
FYI, above file is generated by below systemd unit:
$ dpkg -L unbound
[..]
/lib/systemd/system/unbound-resolvconf.service
And serves below purpose wich is not desired in our use case so we disable it in the guide:
$ systemctl cat unbound-resolvconf.service
# /lib/systemd/system/unbound-resolvconf.service
# This is a helper unit to register local unbound resolver daemon in
# resolv.conf. This is done asyncronously in order not to slow down
# the main unbound service startup, since this will trigger resolvconf
# reload of other services which might be a lengthly procedure.
# See #826241 for the origins of this service.
#
# Can this whole thing be done using ExecStartPost= in unbound.service?
[..]
ExecStart=/usr/libexec/unbound-helper resolvconf_start
But still have to cleanup that generated file afterwards.
I believe its nothing to worry about: