Split up [github] testers (#2560)

- Update github contributors badge for `create-service-tester`.

services/github/github-issue-detail.tester.js

@@ -0,0 +1,68 @@
+'use strict'
+
+const Joi = require('joi')
+const { isFormattedDate } = require('../test-validators')
+
+const t = (module.exports = require('../create-service-tester')())
+
+t.create('github issue state')
+  .get('/s/badges/shields/979.json')
+  .expectJSONTypes(
+    Joi.object().keys({
+      name: 'issue 979',
+      value: Joi.equal('open', 'closed'),
+    })
+  )
+
+t.create('github issue state (repo not found)')
+  .get('/s/badges/helmets/979.json')
+  .expectJSON({
+    name: 'issue/pull request 979',
+    value: 'issue, pull request or repo not found',
+  })
+
+t.create('github issue title')
+  .get('/title/badges/shields/979.json')
+  .expectJSONTypes(
+    Joi.object().keys({
+      name: 'issue 979',
+      value: 'Github rate limits cause transient service test failures in CI',
+    })
+  )
+
+t.create('github issue author')
+  .get('/u/badges/shields/979.json')
+  .expectJSONTypes(Joi.object().keys({ name: 'author', value: 'paulmelnikow' }))
+
+t.create('github issue label')
+  .get('/label/badges/shields/979.json')
+  .expectJSONTypes(
+    Joi.object().keys({
+      name: 'label',
+      value: Joi.equal(
+        'bug | developer-experience',
+        'developer-experience | bug'
+      ),
+    })
+  )
+
+t.create('github issue comments')
+  .get('/comments/badges/shields/979.json')
+  .expectJSONTypes(
+    Joi.object().keys({
+      name: 'comments',
+      value: Joi.number().greater(15),
+    })
+  )
+
+t.create('github issue age')
+  .get('/age/badges/shields/979.json')
+  .expectJSONTypes(
+    Joi.object().keys({ name: 'created', value: isFormattedDate })
+  )
+
+t.create('github issue update')
+  .get('/last-update/badges/shields/979.json')
+  .expectJSONTypes(
+    Joi.object().keys({ name: 'updated', value: isFormattedDate })
+  )