Update README.md (#702)

improved sync section

docs/README.md

@@ -75,3 +75,12 @@ Run the tests and generate the code coverage report:
 Run all checks like the Github CI:
 
     make ci
+
+### Import a commit into customers repo
+
+1. go to customer repo tree
+2. add les tilleuls repo as a remote : `git remote add source git@github.com:coopTilleuls/plateformcoop-ebs.git`
+3. change to sync branch : `git checkout chore/sync-les-tilleuls`
+4. update the branch by merging main : `git merge main`
+5. update source remote : `git fetch source`
+6. cherry-pick the commits you want : `git cherry-pick <commit ref>`