Ensure only one SC is marked as "default"

CHANGELOG.md

@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Component name ([#2])
 - Disable Kapitan plugin ([#4])
+- Non-default StorageClasses have their "is-default-class" annotation removed ([#7])
 
 ### Fixed
 
@@ -25,3 +26,4 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 [#3]: https://github.com/projectsyn/component-storageclass/pull/3
 [#4]: https://github.com/projectsyn/component-storageclass/pull/4
 [#6]: https://github.com/projectsyn/component-storageclass/pull/6
+[#7]: https://github.com/projectsyn/component-storageclass/pull/7

lib/storageclass.libsonnet

@@ -20,7 +20,7 @@ local params = inv.parameters.storageclass;
 local storageClass(name) = kube._Object('storage.k8s.io/v1', 'StorageClass', name) {
   metadata+: {
     annotations+: {
-      [if params.defaultClass == name then 'storageclass.kubernetes.io/is-default-class']: 'true',
+      'storageclass.kubernetes.io/is-default-class': if params.defaultClass == name then 'true' else null,
     },
   },
 } + params.defaults;