[ES|QL] Async implementation of the rule executor.

[afoucret]

Why ?

Currently, the rule executor executor supports only synchronous rules.
This PR is an attempt to add support for asynchronous rules, so we can do async stuffs in the analyzer or logical/physical optimizers.

Changes:

• Rule is now interface instead of an abstract class
• Rule is implemented by two different abstract classes Rule.Sync and Rule.Async that can be used to build synchronous or asynchronous rules
• Existing rules in the analyzer or the optimizers have been migrated to Rule.Sync
• RuleExecutor::execute now has an async version and its sync version has been marked as deprecated
• Added unit tests for RuleExecutor.
• Did the same for ParameterizedRuleExecutor / ParameterizedRule

Performances

./gradlew -p benchmarks run --args QueryPlanningBenchmark                                                                                                                                                                             

Result on main:

Result "org.elasticsearch.benchmark._nightly.esql.QueryPlanningBenchmark.manyFields":
  1.383 ±(99.9%) 0.009 ms/op [Average]
  (min, avg, max) = (1.377, 1.383, 1.396), stdev = 0.006
  CI (99.9%): [1.374, 1.392] (assumes normal distribution)

Benchmark                          Mode  Cnt  Score   Error  Units
QueryPlanningBenchmark.manyFields  avgt   10  1.383 ± 0.009  ms/op

Result on branch:

Result "org.elasticsearch.benchmark._nightly.esql.QueryPlanningBenchmark.manyFields":
  1.264 ±(99.9%) 0.005 ms/op [Average]
  (min, avg, max) = (1.259, 1.264, 1.269), stdev = 0.003
  CI (99.9%): [1.259, 1.269] (assumes normal distribution)

Benchmark                          Mode  Cnt  Score   Error  Units
QueryPlanningBenchmark.manyFields  avgt   10  1.264 ± 0.005  ms/op