obsdiscovery: adopt to calling convention change
Upstream commits 71d83b315778 and abce899c985f changed the calling
convention of setdiscovery._takefullsample().
We inspect the signature of the function before calling it so
we can pass the proper arguments.
#require test-repo
$ checkcm() {
> if ! (which check-manifest > /dev/null); then
> echo skipped: missing tool: check-manifest;
> exit 80;
> fi;
> };
$ checkcm
$ cat << EOF >> $HGRCPATH
> [experimental]
> evolution=all
> EOF
Run check manifest:
$ cd $TESTDIR/..
$ check-manifest
lists of files in version control and sdist match