Fix databricks_cluster is_pinned limit in docs (#1188)

Fix #1184

Author: nfx

docs/resources/cluster.md

@@ -45,7 +45,7 @@ resource "databricks_cluster" "shared_autoscaling" {
 * `spark_env_vars` - (Optional) Map with environment variable key-value pairs to fine-tune Spark clusters. Key-value pairs of the form (X,Y) are exported (i.e., X='Y') while launching the driver and workers.
 * `custom_tags` - (Optional) Additional tags for cluster resources. Databricks will tag all cluster resources (e.g., AWS EC2 instances and EBS volumes) with these tags in addition to `default_tags`.
 * `spark_conf` - (Optional) Map with key-value pairs to fine-tune Spark clusters, where you can provide custom [Spark configuration properties](https://spark.apache.org/docs/latest/configuration.html) in a cluster configuration.
-* `is_pinned` - (Optional) boolean value specifying if cluster is pinned (not pinned by default). You must be a Databricks administrator to use this.  The pinned clusters' maximum number is [limited to 20](https://docs.databricks.com/clusters/clusters-manage.html#pin-a-cluster), so `apply` may fail if you have more than that.
+* `is_pinned` - (Optional) boolean value specifying if cluster is pinned (not pinned by default). You must be a Databricks administrator to use this.  The pinned clusters' maximum number is [limited to 70](https://docs.databricks.com/clusters/clusters-manage.html#pin-a-cluster), so `apply` may fail if you have more than that.
 
 The following example demonstrates how to create an autoscaling cluster with [Delta Cache](https://docs.databricks.com/delta/optimizations/delta-cache.html) enabled: