Add tests to test implementations git head too

config/jenkins.yml

@@ -125,6 +125,22 @@ jobs:
           }
         }
       }
+  - script: >
+      multibranchPipelineJob('r7rs/r7rs-srfi-head') {
+        displayName: 'R7RS-SRFI-head'
+        jenkinsfile: Jenkinsfile-head
+        branchSources {
+          git {
+              id('github')
+              remote('https://github.com/srfi-explorations/r7rs-srfi.git')
+          }
+        }
+        orphanedItemStrategy {
+          discardOldItems {
+              numToKeep(10)
+          }
+        }
+      }
   - script: >
       multibranchPipelineJob('r7rs/r7rs-tests') {
         displayName: 'r7rs-tests'