[concourse] Add support for old_name Job attribute

See: https://github.com/spring-projects/sts4/issues/388

headless-services/concourse-language-server/src/main/java/org/springframework/ide/vscode/concourse/PipelineYmlSchema.java

@@ -407,6 +407,7 @@ public class PipelineYmlSchema implements YamlSchema {
 
 		AbstractType job = f.ybean("Job");
 		addProp(job, "name", jobNameDef).isPrimary(true);
+		addProp(job, "old_name", t_ne_string);
 		addProp(job, "plan", f.yseq(step)).isRequired(true);
 		addProp(job, "serial", t_boolean);
 		addProp(job, "build_logs_to_retain", t_pos_integer);

headless-services/concourse-language-server/src/main/resources/desc/Job/old_name.md

@@ -0,0 +1,16 @@
+*Optional*. The old name of the job. If configured, the history of old job will be inherited to the new one. Once the
+pipeline is set, this field can be removed as the builds have been transfered.
+
+This can be used to rename a job without losing its history, like so:
+
+    jobs:
+    - name: new-name
+      old_name: current-name
+      plan: [get: 10m]
+
+After the pipeline is set, because the builds have been inherited, the job can have the field removed:
+
+    jobs:
+    - name: new-name
+      plan: [get: 10m]
+

headless-services/concourse-language-server/src/test/java/org/springframework/ide/vscode/concourse/ConcourseEditorTest.java

@@ -3985,6 +3985,7 @@ public class ConcourseEditorTest {
 		Editor editor = harness.newEditor(
 				"jobs:\n" +
 				"  - name: job\n" +
+				"    old_name: formerly-known-as\n" +
 				"    serial: true\n" +
 				"    build_logs_to_retain: 10\n" +
 				"    serial_groups: []\n" +
@@ -4013,6 +4014,7 @@ public class ConcourseEditorTest {
 		);
 		editor.assertProblems(/*NONE*/);
 		editor.assertHoverContains("name", "The name of the job");
+		editor.assertHoverContains("old_name", "history of old job will be inherited to the new one");
 		editor.assertHoverContains("serial", "execute one-by-one");
 		editor.assertHoverContains("build_logs_to_retain", "only the last specified number of builds");
 		editor.assertHoverContains("serial_groups", "referencing the same tags will be serialized");
@@ -4031,6 +4033,7 @@ public class ConcourseEditorTest {
 		Editor editor = harness.newEditor(
 				"jobs:\n" +
 				"  - name: job\n" +
+				"    old_name: formerly-known-as\n" +
 				"    serial: isSerial\n" +
 				"    build_logs_to_retain: retainers\n" +
 				"    serial_groups: no-list\n" +
@@ -4094,6 +4097,7 @@ public class ConcourseEditorTest {
 				"ensure",
 				"interruptible",
 				"max_in_flight",
+				"old_name",
 				"on_abort",
 				"on_error",
 				"on_failure",