docs: Minor recommendations prior to v0.34.21 release (#9267)

* Make reindex-event cmd docs consistent with other commands

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Add warning regarding DiscardABCIResponses to BlockResults Go API

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Update OpenAPI spec to reflect discard_abci_responses change

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Add release highlights to CHANGELOG_PENDING

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Add pending changelog entry for #9033

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Format pending changelog entries consistently

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Correct and simplify comment wording

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Remove changelog entry regarding storage section

Signed-off-by: Thane Thomson <connect@thanethomson.com>

Signed-off-by: Thane Thomson <connect@thanethomson.com>

rpc/core/blocks.go

@@ -133,6 +133,7 @@ func Commit(ctx *rpctypes.Context, heightPtr *int64) (*ctypes.ResultCommit, erro
 
 // BlockResults gets ABCIResults at a given height.
 // If no height is provided, it will fetch results for the latest block.
+// When DiscardABCIResponses is enabled, an error will be returned.
 //
 // Results are for the height of the block containing the txs.
 // Thus response.results.deliver_tx[5] is the results of executing

rpc/openapi/openapi.yaml

@@ -712,7 +712,8 @@ paths:
       tags:
         - Info
       description: |
-        Get block_results.
+        Get block_results. When the `discard_abci_responses` storage flag is
+        enabled, this endpoint will return an error.
       responses:
         "200":
           description: Block results.