src: fix IS_LTS and IS_RELEASE flags

Clear the `NODE_VERSION_IS_RELEASE` flag and restore the
`NODE_VERSION_IS_LTS` flag.

PR-URL: #43761
Refs: https://github.com/nodejs/node/runs/7271286633?check_suite_focus=true
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Beth Griggs <bgriggs@redhat.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Ruy Adorno <ruyadorno@github.com>

src/node_version.h

@@ -26,10 +26,10 @@
 #define NODE_MINOR_VERSION 20
 #define NODE_PATCH_VERSION 1
 
-#define NODE_VERSION_IS_LTS 0
+#define NODE_VERSION_IS_LTS 1
 #define NODE_VERSION_LTS_CODENAME "Fermium"
 
-#define NODE_VERSION_IS_RELEASE 1
+#define NODE_VERSION_IS_RELEASE 0
 
 #ifndef NODE_STRINGIFY
 #define NODE_STRINGIFY(n) NODE_STRINGIFY_HELPER(n)