Fix and unmute testTsdbTemplatesNoKeywordFieldType

[felixbarny]

This following was problematic:

.put("index.routing_path", randomBoolean() ? null : "metricset")

Because it set an explicit null as the routing path`.

In cases where the following evaluates to false, this leads to an error rightfully complaining that the routing path is required:

.put("index.dimensions_tsid_strategy_enabled", randomDouble() < 0.8)

[elasticsearchmachine]

Pinging @elastic/es-storage-engine (Team:StorageEngine)

[kkrik-es]

Shouldn't this also be always set when the setting above is false?

[kkrik-es]

I'd simply fix as:

boolean dimensions_tsid_strategy_enabled = randomDouble() < 0.8;
...
          .put("index.routing_path", dimensions_tsid_strategy_enabled || randomBoolean() ? "metricset" : null)
          .put("index.dimensions_tsid_strategy_enabled", dimensions_tsid_strategy_enabled)

[felixbarny]

Shouldn't this also be always set when the setting above is false?

No, even if index.dimensions_tsid_strategy_enabled is false, the routing_path doesn't need to be set explicitly as this is a data stream template, for which the routing_path will be automatically determined if unset. I explicitly want to test all four permutations of strategy enabled true/false and routing path set/unset. Also, routing path unset is different to routing path explicitly set to null. This triggered the test failure in the first place. It's a bit surprising but not sure if it's worth changing. At least not in this PR.

As both explicitly setting index.routing_path as well setting index.dimensions_tsid_strategy_enable to false disables the new index.dimensions-based tsid strategy, I wanted to give disabling that strategy a lower probability with via randomDouble() < 0.8.

[felixbarny]

Note that I also ran this locally with 500 iterations and all have succeeded.