Add a job to check zot config examples (and fix existing examples) (#2322)

* fix: Add credentials config verification

(cherry picked from commit e7fdfa0bcc)
Signed-off-by: Andrei Aaron <aaaron@luxoft.com>

* fix: Update golang version to 1.21.x

Signed-off-by: onidoru <25552941+onidoru@users.noreply.github.com>
Signed-off-by: Nikita Kotikov <25552941+onidoru@users.noreply.github.com>
(cherry picked from commit cbc0f89dfb)
Signed-off-by: Andrei Aaron <aaaron@luxoft.com>

* fix: LDAP credentials files are now required, add more tests

Signed-off-by: onidoru <25552941+onidoru@users.noreply.github.com>
Signed-off-by: Nikita Kotikov <25552941+onidoru@users.noreply.github.com>
(cherry picked from commit b74366d50b)
Signed-off-by: Andrei Aaron <aaaron@luxoft.com>

* fix: Update error handling, add more tests

Signed-off-by: onidoru <25552941+onidoru@users.noreply.github.com>
Signed-off-by: Nikita Kotikov <25552941+onidoru@users.noreply.github.com>
(cherry picked from commit 8a61bbc2d4)
Signed-off-by: Andrei Aaron <aaaron@luxoft.com>

* fix: Add coverage

Signed-off-by: Andrei Aaron <aaaron@luxoft.com>

---------

Signed-off-by: onidoru <25552941+onidoru@users.noreply.github.com>
Signed-off-by: Nikita Kotikov <25552941+onidoru@users.noreply.github.com>
Signed-off-by: Andrei Aaron <aaaron@luxoft.com>
Co-authored-by: onidoru <onidoru@yahoo.com>
Co-authored-by: Nikita Kotikov <25552941+onidoru@users.noreply.github.com>

examples/config-example.json

@@ -18,8 +18,7 @@
         "startTLS": false,
         "baseDN": "ou=Users,dc=example,dc=org",
         "userAttribute": "uid",
-        "bindDN": "cn=ldap-searcher,ou=Users,dc=example,dc=org",
-        "bindPassword": "ldap-searcher-password",
+        "credentialsFile": "examples/config-ldap-credentials.json",
         "skipVerify": false,
         "subtreeSearch": true
       },