tests: Ignore symbol-versions in nm output

The Debian 11 toolchain produces them like this.

Signed-off-by: Simon McVittie <smcv@collabora.com>
6 jobs for master in 8 minutes and 20 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
manual #79771
allowed to fail manual
build:arch
passed #79767
build:asan

00:03:28

passed #79770
build:bionic

00:08:18

passed #79769
build:buster

00:07:51

passed #79768
build:stretch

00:08:19

passed #79766
build:ubsan

00:03:25