added username and password auth to snowflake known issue (#822)

This issue also affected username and password authentication (which
isn't deprecated yet)

Author: gerardma77

content/vault/global/partials/important-changes/summary-tables/1_19.mdx

@@ -39,3 +39,4 @@ Found  | Fixed  | Workaround | Edition    | Issue
 1.19.0 | 1.19.4 | **Yes**    | Enterprise | [External Enterprise plugins cannot run on a standby node when it becomes active](/vault/docs/v1.19.x/updates/important-changes#external-ent-plugins)
 1.19.0 | 1.19.1 | Upgrade    | All        | [Vault log file missing subsystem logs](/vault/docs/v1.19.x/updates/important-changes#missing-logs)
 1.19.1 | 1.19.4 | **Yes**    | All        | [Azure authN fails to authenticate Uniform VMSS instances](/vault/docs/v1.19.x/updates/important-changes#azure-vmss)
+1.18.4 | No     | **Yes**    | All        | [Failing credential refresh for Snowflake DB secrets engine key pair authentication](/vault/docs/v1.19.x/updates/important-changes#snowflake-keypair-refresh)

content/vault/global/partials/important-changes/summary-tables/1_20.mdx

@@ -25,5 +25,5 @@ Found  | Fixed  | Workaround | Edition    | Issue
 1.20.0 | 1.20.1 | **Yes**    | Enterprise | [Secondary cluster reload overwrites development cluster setting](/vault/docs/v1.20.x/updates/important-changes#development-cluster-reload)
 1.20.0 | 1.20.1 | **Yes**    | All        | [UI login fails for auth mounts with underscores and unauthenticated listing](/vault/docs/v1.20.x/updates/important-changes#ui-login-underscore)
 1.20.0 | 1.20.1 | **Yes**    | All        | [GUI navigation error for KV v2 secret paths containing underscores](/vault/docs/v1.20.x/updates/important-changes#ui-kvv2-underscore-secrets)
-1.20.0 | 1.20.1 | **Yes**    | All        | [Failing credential refresh for Snowflake DB secrets engine key pair authentication](/vault/docs/v1.20.x/updates/important-changes#snowflake-keypair-refresh)
+1.18.4 | No     | **Yes**    | All        | [Failing credential refresh for Snowflake DB secrets engine key pair authentication](/vault/docs/v1.20.x/updates/important-changes#snowflake-keypair-refresh)
 1.20.0 | 1.20.1 | **Yes**    | All        | [Duplicate LDAP password rotations on standby node check-in](/vault/docs/v1.20.x/updates/important-changes#ldap-checkin)

content/vault/v1.19.x/content/docs/updates/important-changes.mdx

@@ -431,3 +431,15 @@ to the billing start date for the cluster.
 To avoid issues and unexpected behavior with Vault Community, always provide a
 valid `start_time` value when calling `/sys/internal/counters/activity` or
 upgrade to v1.20.x.
+
+### Failing credential refresh for Snowflake DB secrets engine key pair authentication ((#snowflake-keypair-refresh))
+
+| Change      | Affected version                       | Fixed version
+| ----------- | -------------------------------------- | --------------------
+| Known issue | 1.20.x, 1.19.x, 1.18.x+ent, 1.17.x+ent, 1.16.x+ent | None
+
+Users using keypair or username and password authentication with Snowflake databases may receive errors
+due to improper credential refreshes and stale connections in the connection pool.
+When two or more concurrent operations occur, Vault tries to reuse an idle
+connection from the pool and the request fails due to session timeout in the
+Snowflake database.

content/vault/v1.20.x/content/docs/updates/important-changes.mdx

@@ -296,7 +296,7 @@ You can also use the API explorer to make any HTTP request:
 | ----------- | -------------------------------------- | --------------------
 | Known issue | 1.20.x, 1.19.x, 1.18.x+ent, 1.17.x+ent, 1.16.x+ent | None
 
-Users using keypair authentication with Snowflake databases may receive errors
+Users using keypair or username and password authentication with Snowflake databases may receive errors
 due to improper credential refreshes and stale connections in the connection pool.
 When two or more concurrent operations occur, Vault tries to reuse an idle
 connection from the pool and the request fails due to session timeout in the