cli-plugins/manager: fix deprecation comment of Metadata.Experimental

This field was marked deprecated in 977d3ae,
which is part of v20.10 and up, but the comment was missing a newline before
the deprecation message, which may be picked up by IDEs, but is not matching
the correct format, so may not be picked up by linters.

This patch fixes the format, to make sure linters pick up that the field is
deprecated.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit 72e3813)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

cli-plugins/manager/metadata.go

@@ -23,6 +23,7 @@ type Metadata struct {
 	// URL is a pointer to the plugin's homepage.
 	URL string `json:",omitempty"`
 	// Experimental specifies whether the plugin is experimental.
+	//
 	// Deprecated: experimental features are now always enabled in the CLI
 	Experimental bool `json:",omitempty"`
 }