update softwares to:
  - grafana 7.4.3
  - telegrah 1.17.3
  - influxdb 1.8.4
  - loki current master ( 2.1.0 )

and components to:
  - golang 1.16
  - nodejs 14.16.0
  - yarn 1.22.10
  - python 3.7

This new loki version supports parsing multi-line logs, as demonstrated in
the updated test.

Since this version we also remove cache at the end of build, which
makes the software directory smaller and accessorily prevent test failures
during the ldd checks from checkSoftware with some binaries in the cache.