fix: added download url for debian 9 (#67)

* added download url for debian 9

* fixed error, added brace

* adjust the test

Author: asteinbps

src/util/MongoBinaryDownloadUrl.js

@@ -122,7 +122,9 @@ export default class MongoBinaryDownloadUrl {
   getDebianVersionString(os: OS): string {
     let name: string = 'debian';
     const release: number = parseFloat(os.release);
-    if (release >= 8.1) {
+    if (release >= 9) {
+      name += '92';
+    } else if (release >= 8.1) {
       name += '81';
     } else if (release >= 7.1) {
       name += '71';

src/util/__tests__/MongoBinaryDownloadUrl-test.js

@@ -177,7 +177,7 @@ describe('MongoBinaryDownloadUrl', () => {
           dist: 'debian',
           release: '9.0',
         })
-      ).toBe('debian81');
+      ).toBe('debian92');
     });
   });