improvement(scylla-bench): bump the scylla-bench version

The 'v0.1.20' scylla-bench version utilizes the gocql driver that
supports Scylla 'tablets' feature and fixes the issue discovered in v0.1.19.
So, start using it to be able to cover that feature in our tests.

defaults/test_default.yaml

@@ -209,7 +209,7 @@ stress_image:
   ycsb: 'scylladb/hydra-loaders:ycsb-jdk8-20220918'
   nosqlbench: 'scylladb/hydra-loaders:nosqlbench-4.15.49'
   cassandra-stress: '' # default would be same version as scylla under test
-  scylla-bench: 'scylladb/hydra-loaders:scylla-bench-v0.1.18'
+  scylla-bench: 'scylladb/hydra-loaders:scylla-bench-v0.1.20'
   gemini: 'scylladb/hydra-loaders:gemini-v1.8.6'
   alternator-dns: 'scylladb/hydra-loaders:alternator-dns-0.1'
   cdc-stresser: 'scylladb/hydra-loaders:cdc-stresser-20210630'

docs/configuration_options.md

@@ -338,7 +338,7 @@
 | **<a href="#user-content-nemesis_multiply_factor" name="nemesis_multiply_factor">nemesis_multiply_factor</a>**  | Multiply the list of nemesis to execute by the specified factor | 6 | SCT_NEMESIS_MULTIPLY_FACTOR
 | **<a href="#user-content-raid_level" name="raid_level">raid_level</a>**  | Number of of raid level: 0 - RAID0, 5 - RAID5 | N/A | SCT_RAID_LEVEL
 | **<a href="#user-content-bare_loaders" name="bare_loaders">bare_loaders</a>**  | Don't install anything but node_exporter to the loaders during cluster setup | N/A | SCT_BARE_LOADERS
-| **<a href="#user-content-stress_image" name="stress_image">stress_image</a>**  | Dict of the images to use for the stress tools | {'ndbench': 'scylladb/hydra-loaders:ndbench-jdk8-20210720', 'ycsb': 'scylladb/hydra-loaders:ycsb-jdk8-20220918', 'nosqlbench': 'scylladb/hydra-loaders:nosqlbench-4.15.49', 'cassandra-stress': '', 'scylla-bench': 'scylladb/hydra-loaders:scylla-bench-v0.1.18', 'gemini': 'scylladb/hydra-loaders:gemini-v1.8.6', 'alternator-dns': 'scylladb/hydra-loaders:alternator-dns-0.1', 'cdc-stresser': 'scylladb/hydra-loaders:cdc-stresser-20210630', 'kcl': 'scylladb/hydra-loaders:kcl-jdk8-20210526-ShardSyncStrategyType-PERIODIC', 'harry': 'scylladb/hydra-loaders:cassandra-harry-jdk11-20220816', 'latte': 'scylladb/hydra-loaders:latte-rust1_73-20231025'} | SCT_STRESS_IMAGE
+| **<a href="#user-content-stress_image" name="stress_image">stress_image</a>**  | Dict of the images to use for the stress tools | {'ndbench': 'scylladb/hydra-loaders:ndbench-jdk8-20210720', 'ycsb': 'scylladb/hydra-loaders:ycsb-jdk8-20220918', 'nosqlbench': 'scylladb/hydra-loaders:nosqlbench-4.15.49', 'cassandra-stress': '', 'scylla-bench': 'scylladb/hydra-loaders:scylla-bench-v0.1.20', 'gemini': 'scylladb/hydra-loaders:gemini-v1.8.6', 'alternator-dns': 'scylladb/hydra-loaders:alternator-dns-0.1', 'cdc-stresser': 'scylladb/hydra-loaders:cdc-stresser-20210630', 'kcl': 'scylladb/hydra-loaders:kcl-jdk8-20210526-ShardSyncStrategyType-PERIODIC', 'harry': 'scylladb/hydra-loaders:cassandra-harry-jdk11-20220816', 'latte': 'scylladb/hydra-loaders:latte-rust1_73-20231025'} | SCT_STRESS_IMAGE
 | **<a href="#user-content-enable_argus" name="enable_argus">enable_argus</a>**  | Control reporting to argus | True | SCT_ENABLE_ARGUS
 | **<a href="#user-content-cs_populating_distribution" name="cs_populating_distribution">cs_populating_distribution</a>**  | set c-s parameter '-pop' with gauss/uniform distribution for<br>performance gradual throughtput grow tests | N/A | SCT_CS_POPULATING_DISTRIBUTION
 | **<a href="#user-content-num_loaders_step" name="num_loaders_step">num_loaders_step</a>**  | Number of loaders which should be added per step | N/A | SCT_NUM_LOADERS_STEP