There were several issues; clearly the tests hadn't been run in a while.

- gcrypt11 isn't available in the docker image, I'd guess this broke
  when I updated `yottadb-base` from ubuntu 18.04 to 20.04 a while back.
  gcrypt20 is available and I switched to that.

- I then got an error about icu-config:

  ```
  Step 5/12 : RUN mkdir /tmp/plugin-build &&     cd /tmp/plugin-build &&     cp /opt/yottadb/current/plugin/gtmcrypt/source.tar . &&     tar -xf source.tar &&     . /opt/yottadb/gui/env &&     make && make install && make clean &&     find $ydb_dist/plugin -type f -exec chown root:root {} +
   ---> Running in 13a20c8e6b2f
  /bin/sh: 31: /opt/yottadb/gui/env: icu-config: not found
  ```

  I fixed it by using `pkg-config` instead; `icu-config` is deprecated.

- There was an error about the Node version not matching:

  ```
  Downloading https://nodejs.org/dist/v14.15.5/node-v14.15.5-linux-x64.tar.gz...
  ######################################################################## 100.0%
  Computing checksum with sha256sum
  Checksums matched!
  nvm is not compatible with the npm config "prefix" option: currently set to "/usr/bin/versions/node/v14.15.5"
  Run `nvm use --delete-prefix v14.15.5` to unset it.
  ```

  On inspection it turned out we were using an old version of nvm; I updated it to the latest release.

The image now builds and the tests pass, although there are a metric ton
of warnings. I can work on those if you think it's worthwhile.