PLT-6965 jira integration (plus plugin scaffolding) (#6918)

* plugin scaffolding / jira integration

* add vendored testify packages

* webhook fix

* don't change i18n ids

* support configuration watching

* add basic jira plugin configuration to admin console

* fix eslint errors

* fix another eslint warning

* polish

* undo unintentional config.json commit >:(

* test fix

* add jira plugin diagnostics, remove dm support, add bot tag, generate web-safe secrets

* rebase, implement requested changes

* requested changes

* remove tests and minimize makefile change

* add missing license headers

* add missing comma

* remove bad line from Makefile

webapp/components/admin_console/admin_sidebar.jsx

@@ -522,6 +522,15 @@ export default class AdminSidebar extends React.Component {
                                         />
                                     }
                                 />
+                                <AdminSidebarSection
+                                    name='jira'
+                                    title={
+                                        <FormattedMessage
+                                            id='admin.sidebar.jira'
+                                            defaultMessage='JIRA (Beta)'
+                                        />
+                                    }
+                                />
                                 {webrtcSettings}
                                 <AdminSidebarSection
                                     name='external'