Fix some typos in plugins & reference docs (elastic#84667)

This pull request removes a few instances of duplicate words or
punctuation and erroneous spelling from the docs.

docs/plugins/analysis-icu.asciidoc

@@ -442,7 +442,7 @@ unless otherwise specified in the collation.
 Possible values: `no` (default, but collation-dependent) or `canonical`.
 Setting this decomposition property to `canonical` allows the Collator to
 handle unnormalized text properly, producing the same results as if the text
-were normalized. If `no` is set, it is the user's responsibility to insure
+were normalized. If `no` is set, it is the user's responsibility to ensure
 that all text is already in the appropriate form before a comparison or before
 getting a CollationKey. Adjusting decomposition mode allows the user to select
 between faster and more complete collation behavior. Since a great many of the

docs/plugins/plugin-script.asciidoc

@@ -301,7 +301,7 @@ plugin configuration file.
 If you run {es} using Docker, you can manage plugins using a declarative configuration file.
 When {es} starts up, it will compare the plugins in the file with those
 that are currently installed, and add or remove plugins as required. {es}
-will also upgrade offical plugins when you upgrade {es} itself.
+will also upgrade official plugins when you upgrade {es} itself.
 
 The file is called `elasticsearch-plugins.yml`, and must be placed in the
 Elasticsearch configuration directory, alongside `elasticsearch.yml`. Here

docs/reference/aggregations/bucket/variablewidthhistogram-aggregation.asciidoc

@@ -74,7 +74,7 @@ TIP: A shard can return fewer than `shard_size` buckets, but it cannot return mo
 
 ==== Shard size
 The `shard_size` parameter specifies the number of buckets that the coordinating node will request from each shard.
-A higher `shard_size` leads each shard to produce smaller buckets. This reduce the likelihood of buckets overlapping
+A higher `shard_size` leads each shard to produce smaller buckets. This reduces the likelihood of buckets overlapping
 after the reduction step. Increasing the `shard_size` will improve the accuracy of the histogram, but it will
 also make it more expensive to compute the final result because bigger priority queues will have to be managed on a
 shard level, and the data transfers between the nodes and the client will be larger.

docs/reference/analysis/tokenfilters/synonym-graph-tokenfilter.asciidoc

@@ -99,7 +99,7 @@ stop word.
 ==== `tokenizer` and `ignore_case` are deprecated
 
 The `tokenizer` parameter controls the tokenizers that will be used to
-tokenize the synonym, this parameter is for backwards compatibility for indices that created before 6.0..
+tokenize the synonym, this parameter is for backwards compatibility for indices that created before 6.0.
 The `ignore_case` parameter works with `tokenizer` parameter only.
 
 Two synonym formats are supported: Solr, WordNet.

docs/reference/commands/keystore.asciidoc

@@ -91,7 +91,7 @@ names can be specified as arguments to the `remove` command.
 `show <setting>`:: Displays the value of a single setting in the keystore.
 Pass the `-o` (or `--output`) parameter to write the setting to a file.
 If writing to the standard output (the terminal) the setting's value is always
-interpretted as a UTF-8 string. If the setting contains binary data (for example
+interpreted as a UTF-8 string. If the setting contains binary data (for example
 for data that was added via the `add-file` command), always use the `-o` option
 to write to a file.
 

docs/reference/fleet/fleet-search.asciidoc

@@ -23,7 +23,7 @@ only be executed on local shards after the all operations up to and including th
 sequence number checkpoint are visible for search. Indexed operations become visible after a
 refresh. The checkpoints are indexed by shard.
 
-If a timeout occurs before the the checkpoint has been refreshed into Elasticsearch,
+If a timeout occurs before the checkpoint has been refreshed into Elasticsearch,
 the search request will timeout.
 
 The fleet search API only supports searches against a single target. If an index alias

docs/reference/indices/shrink-index.asciidoc

@@ -171,7 +171,7 @@ POST /my_source_index/_shrink/my_target_index
 
 <1> The number of shards in the target index. This must be a factor of the
     number of shards in the source index.
-<2> Best compression will only take affect when new writes are made to the
+<2> Best compression will only take effect when new writes are made to the
     index, such as when <<indices-forcemerge,force-merging>> the shard to a single
     segment.