[master] 66860cd0a coverity: Only run in the main repository

[Dridi Boukelmoune]

commit 66860cd0ac1b09b67b2e0288d25ba810f2ccad2e
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Mon Jun 20 11:26:16 2022 +0200

    coverity: Only run in the main repository
    
    Otherwise forks may attempt to run coveriy scan builds only to fail and
    spam their owners.

diff --git a/.github/workflows/coverity.yml b/.github/workflows/coverity.yml
index aa7a85f12..6843d91bd 100644
--- a/.github/workflows/coverity.yml
+++ b/.github/workflows/coverity.yml
@@ -7,6 +7,7 @@ on:
 
 jobs:
   coverity:
+    if: github.repository_owner == 'varnishcache'
     runs-on: ubuntu-latest
     steps:
       - run: |