Update help messages of CLI commands

docs/cli/build/in-copr.md

@@ -42,6 +42,9 @@ for more details). Alternatively you can use copr API token available [here](htt
       PATH_OR_URL argument is a local path or a URL to the upstream git
       repository, it defaults to the current working directory.
 
+      Copr configuration needs to be set before usage.
+      https://docs.pagure.org/copr.copr/user_documentation.html#quick-start
+
     Options:
       --wait / --no-wait              Wait for the build to finish
       --owner TEXT                    Copr user, owner of the project. (defaults

docs/cli/build/in-mock.md

@@ -40,6 +40,7 @@ packit build in-mock --root=fedora-40-x86_64
       -r, --root TEXT           Uses specified chroot configuration. If ends with
                                 '.cfg', then it is treated as full path to the
                                 mock configuration.
+      --default-resultdir       Use the default result directory from mock
       --resultdir DIRECTORY     Specifies the resultdir option for ‹mock› command,
                                 for details see mock(1)
       -p, --package TEXT        Package to build, if more than one available, like

docs/cli/config/validate.md

@@ -19,8 +19,11 @@ Validate the Packit configuration file.
       - checks whether monitoring is enabled if 'pull_from_upstream` is used
 
       PATH_OR_URL argument is a local path or a URL to a git repository with
-      packit configuration file
+      packit configuration file config: Optional path to a specific Packit
+      configuration file.
 
     Options:
-      --offline   Do not make remote API calls requiring network access.
-      -h, --help  Show this message and exit.
+      --offline               Do not make remote API calls requiring network
+                              access.
+      -c, --config-path PATH  Path to a specific Packit configuration file.
+      -h, --help              Show this message and exit.