Building the images fails
Building the images fails during the building of the prometheus exporter step:
#169 [docker-compose_tango-prometheus-exporter 3/5] ADD ska-tango-grafana-exporter/exporter/code /code
#169 sha256:4f146eca9cc23237777e5acd17d35366cea9a060accf17d53a3942833ab41992
#169 ERROR: "/ska-tango-grafana-exporter/exporter/code" not found: not found
and
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> [docker-compose_tango-prometheus-exporter 3/5] ADD ska-tango-grafana-exporter/exporter/code /code:
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failed to solve: rpc error: code = Unknown desc = failed to compute cache key: "/ska-tango-grafana-exporter/exporter/code" not found: not found
make: *** [build] Error 17