podman-login: add page (tldr-pages#14915)

Co-authored-by: Lena <126529524+acuteenvy@users.noreply.github.com>

pages/common/podman-login.md

@@ -0,0 +1,17 @@
+# podman login
+
+> Log in to a container registry.
+> Note: the default authfile path on Linux is `$XDG_RUNTIME_DIR/containers/auth.json`, which is usually stored in a `tmpfs` (in RAM).
+> More information: <https://docs.podman.io/en/latest/markdown/podman-login.1.html>.
+
+- Log in to a registry (non-persistent on Linux; persistent on Windows/macOS):
+
+`podman login {{registry.example.org}}`
+
+- Log in to a registry persistently on Linux:
+
+`podman login --authfile $HOME/.config/containers/auth.json {{registry.example.org}}`
+
+- Log in to an insecure (HTTP) registry:
+
+`podman login --tls-verify false {{registry.example.org}}`