doc: fix historical experimental fetch flag

PR-URL: nodejs#51506
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

doc/api/globals.md

@@ -484,7 +484,7 @@ changes:
     description: No longer experimental.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41811
-    description: No longer behind `--experimental-global-fetch` CLI flag.
+    description: No longer behind `--experimental-fetch` CLI flag.
 -->
 
 > Stability: 2 - Stable
@@ -514,7 +514,7 @@ changes:
     description: No longer experimental.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41811
-    description: No longer behind `--experimental-global-fetch` CLI flag.
+    description: No longer behind `--experimental-fetch` CLI flag.
 -->
 
 > Stability: 2 - Stable
@@ -553,7 +553,7 @@ changes:
     description: No longer experimental.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41811
-    description: No longer behind `--experimental-global-fetch` CLI flag.
+    description: No longer behind `--experimental-fetch` CLI flag.
 -->
 
 > Stability: 2 - Stable
@@ -901,7 +901,7 @@ changes:
     description: No longer experimental.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41811
-    description: No longer behind `--experimental-global-fetch` CLI flag.
+    description: No longer behind `--experimental-fetch` CLI flag.
 -->
 
 > Stability: 2 - Stable
@@ -921,7 +921,7 @@ changes:
     description: No longer experimental.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41811
-    description: No longer behind `--experimental-global-fetch` CLI flag.
+    description: No longer behind `--experimental-fetch` CLI flag.
 -->
 
 > Stability: 2 - Stable