add ascend engine spec (#14682)

docs/src/pages/docs/Connecting to Databases/ascend.mdx

@@ -0,0 +1,17 @@
+---
+name: Ascend.io
+menu: Connecting to Databases
+route: /docs/databases/ascend
+index: 7
+version: 1
+---
+
+## Ascend.io
+
+The recommended connector library to Ascend.io is [impyla](https://github.com/cloudera/impyla).
+
+The expected connection string is formatted as follows:
+
+```
+ascend://{username}:{password}@{hostname}:{port}/{database}?auth_mechanism=PLAIN;use_ssl=true
+```

docs/src/pages/docs/Connecting to Databases/index.mdx

@@ -33,6 +33,7 @@ A list of some of the recommended packages.
 |[Apache Pinot](/docs/databases/pinot)|```pip install pinotdb```|```pinot://BROKER:5436/query?server=http://CONTROLLER:5983/```|
 |[Apache Solr](/docs/databases/solr)|```pip install sqlalchemy-solr```|```solr://{username}:{password}@{hostname}:{port}/{server_path}/{collection}```
 |[Apache Spark SQL](/docs/databases/spark-sql)|```pip install pyhive```|```hive://hive@{hostname}:{port}/{database}```
+|[Ascend.io](/docs/databases/ascend)|```pip install impyla```|```ascend://{username}:{password}@{hostname}:{port}/{database}?auth_mechanism=PLAIN;use_ssl=true```|
 |[Azure MS SQL](/docs/databases/sql-server)|```pip install pymssql``` |```mssql+pymssql://UserName@presetSQL:TestPassword@presetSQL.database.windows.net:1433/TestSchema```
 |[Big Query](/docs/databases/bigquery)|```pip install pybigquery```|```bigquery://{project_id}```|
 |[ClickHouse](/docs/databases/clickhouse)|```pip install clickhouse-driver==0.2.0 && pip install clickhouse-sqlalchemy==0.1.6```|```clickhouse+native://{username}:{password}@{hostname}:{port}/{database}```|