Minor fix in wopi-validator.md

Author: glpatcern

test/wopi-validator.md

@@ -4,7 +4,7 @@ These notes have been adaped from the enterprise ownCloud WOPI implementation, c
 
 1. Setup your WOPI server as well as Reva as required. Make sure the WOPI storage interface unit tests pass.
 
-2. Create an empty folder and touch an file named `test.wopitest` in that folder. For a local Reva setup:
+2. Create an empty folder and touch a file named `test.wopitest` in that folder. For a local Reva setup:
 
    `mkdir /var/tmp/reva/data/einstein/wopivalidator && touch /var/tmp/reva/data/einstein/wopivalidator/test.wopitest`.
 
@@ -14,6 +14,8 @@ These notes have been adaped from the enterprise ownCloud WOPI implementation, c
 
    `curl -H "Authorization: Bearer <wopisecret>" "http://your_wopi_server:port/wopi/iop/test?filepath=<your_file>&endpoint=<your_storage_endpoint>&usertoken=<your_user_credentials_or_id>"`
 
-5. Run the testsuite (you can select a specific test group passing as well e.g. `-e WOPI_TESTGROUP=FileVersion`):
+5. Run the testsuite:
 
    `docker run --rm --add-host="localhost:<your_external_wopiserver_IP>" <output from step 4> deepdiver/wopi-validator-core-docker:latest`
+
+   If you want to select a specific test group, add `-e WOPI_TESTGROUP=<group>` (e.g. `-e WOPI_TESTGROUP=FileVersion`) to the above command.