Prometheus Exporter broken in v0.9.1

Describe the bug
When using v0.9.1 we are getting following error on the exporter container:

Warning  Failed     10m (x3 over 10m)   kubelet            Error: failed to create containerd task: failed to create shim task: OCI runtime create failed: runc create failed: unable to start container process: exec: "/exporter/prometheus_varnish_exporter": stat /exporter/prometheus_varnish_exporter: no such file or directory: unknown

To Reproduce
Just pull image locally and run the prometheus exporter command:

$ docker run -it --rm --entrypoint "/bin/bash" quay.io/mittwald/kube-httpcache:v0.9.1 /exporter/prometheus_varnish_exporter
/bin/bash: /exporter/prometheus_varnish_exporter: No such file or directory

Expected behavior
Error should not happen and does not happen in v0.9.0

Additional context
the symlinked file is missing in the /exporter folder:

$ docker run -it --rm --entrypoint "ls" quay.io/mittwald/kube-httpcache:v0.9.1 -l /exporter/
total 24
-rw-r--r-- 1 1001  118 5464 Jul 15 12:55 CHANGELOG.md
-rw-r--r-- 1 1001  118 1078 Jul 15 12:55 LICENSE
-rw-r--r-- 1 1001  118 5705 Jul 15 12:55 README.md
lrwxrwxrwx 1 root root   84 Jul 15 13:12 prometheus_varnish_exporter -> /exporter/prometheus_varnish_exporter-v1.7.0.linux-amd64/prometheus_varnish_exporter

Start by comparing the v0.9.1 and v0.9.0 container images, focusing on the /exporter/prometheus_varnish_exporter entry point and its symlink target. Reproduce with the documented docker run and ls commands; done means the v0.9.1 exporter command starts successfully and the expected file is present in /exporter.