Fix typo in document of stable jenkins (#22847)

Signed-off-by: tottoto <tottotodev@gmail.com>

stable/jenkins/Chart.yaml

@@ -1,7 +1,7 @@
 apiVersion: v1
 name: jenkins
 home: https://jenkins.io/
-version: 2.1.1
+version: 2.1.2
 appVersion: lts
 description: Open source continuous integration server. It supports multiple SCM tools
   including CVS, Subversion and Git. It can execute Apache Ant and Apache Maven-based

stable/jenkins/README.md

@@ -302,7 +302,7 @@ Some third-party systems, e.g. GitHub, use HTML-formatted data in their payload
 | `agent.podName`            | Agent Pod base name                             | Not set                |
 | `agent.idleMinutes`        | Allows the Pod to remain active for reuse       | 0                      |
 | `agent.yamlTemplate`       | The raw yaml of a Pod API Object to merge into the agent spec | Not set  |
-| `agent.yamlMergeStrategy   | Defines how the raw yaml field gets merged with yaml definitions from inherited pod templates | `override` |
+| `agent.yamlMergeStrategy`  | Defines how the raw yaml field gets merged with yaml definitions from inherited pod templates | `override` |
 | `agent.slaveConnectTimeout`| Timeout in seconds for an agent to be online    | 100                    |
 | `agent.podTemplates`       | Configures extra pod templates for the default kubernetes cloud | `{}`   |
 | `agent.workingDir`         | Configure working directory for default agent   | `/home/jenkins`        |