doc: mark --jitless as experimental

It's already documented as such, but it doesn't have the label.

PR-URL: #51247
Reviewed-By: Marco Ippolito <[email protected]>
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Gerhard Stöbich <[email protected]>
Reviewed-By: Akhil Marsonya <[email protected]>

Author: aduh95

doc/api/cli.md

@@ -1266,13 +1266,13 @@ Opens the REPL even if stdin does not appear to be a terminal.
 added: v12.0.0
 -->
 
+> Stability: 1 - Experimental. This flag is inherited from V8 and is subject to
+> change upstream.
+
 Disable [runtime allocation of executable memory][jitless]. This may be
 required on some platforms for security reasons. It can also reduce attack
 surface on other platforms, but the performance impact may be severe.
 
-This flag is inherited from V8 and is subject to change upstream. It may
-disappear in a non-semver-major release.
-
 ### `--max-http-header-size=size`
 
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