fix jsonnet error with kube-prometheus >= v0.8 (lensapp#5687)

* fix jsonnet error with kube-prometheus > v0.8

kubelet ServiceMonitor moved to kubernetesControlPlane starting from v0.8

Signed-off-by: elvis chan <[email protected]>

* Add not in custom-prometheuus.md about jsonnet version

Signed-off-by: Sebastian Malton <[email protected]>

Signed-off-by: elvis chan <[email protected]>
Signed-off-by: Sebastian Malton <[email protected]>
Co-authored-by: Sebastian Malton <[email protected]>

Author: elvischan-crypto

jsonnet/lens/custom-prometheus.jsonnet

@@ -24,7 +24,7 @@
       },
     },
   },
-  prometheus+:: {
+  kubernetesControlPlane+:: {
     serviceMonitorKubelet+: {
       spec+: {
         endpoints: std.map(function(endpoint)

troubleshooting/custom-prometheus.md

@@ -31,14 +31,15 @@ metricRelabelings:
 
 ### Jsonnet
 
-The required label replacements are bundled in [jsonnet/lens/custom-prometheus](../jsonnet/lens/custom-prometheus.jsonnet). To install it copy the file or use
-[Jsonnet Bundler](https://github.com/jsonnet-bundler/jsonnet-bundler).
+The required label replacements are bundled in [jsonnet/lens/custom-prometheus](../jsonnet/lens/custom-prometheus.jsonnet).
+This file is currently for jsonnet versions >= 0.8.0
+To install it copy the file or use [Jsonnet Bundler](https://github.com/jsonnet-bundler/jsonnet-bundler).
 
 ```bash
 jb init && jb install https://github.com/lensapp/lens/jsonnet/lens@master
 ```
 
-When the installation was successful include it into your definitions. Using the [example](https://github.com/coreos/kube-prometheus#compiling) 
+When the installation was successful include it into your definitions. Using the [example](https://github.com/coreos/kube-prometheus#compiling)
 of kube-prometheus, e.g.:
 
 ```
@@ -60,4 +61,3 @@ local kp =
 ```
 helm upgrade --set server.global.scrape_interval=30s prometheus stable/prometheus
 ```
-