doc: fix incorrect default for maxHeadersCount

request.maxHeadersCount and server.maxHeadersCount were documented
with a default of 2000. The underlying parser limit,
MAX_HEADER_PAIRS in lib/_http_common.js, is a count of name/value
pairs (2 slots per header), so the effective maximum number of
headers is 1000, not 2000.

Verified against a running server: sending 1000 headers returns all
of them, while sending 1001 headers still returns only 1000, with
the extra header silently dropped.

Fixes: #65470
Signed-off-by: suraj-shrivastav <suraj.shrivastavvv@gmail.com>

Author: suraj-shrivastav

doc/api/http.md

@@ -1127,7 +1127,7 @@ const hasContentType = request.hasHeader('content-type');
 
 ### `request.maxHeadersCount`
 
-* Type: {number} **Default:** `2000`
+* Type: {number} **Default:** `1000`
 
 Limits maximum response headers count. If set to 0, no limit will be applied.
 
@@ -1914,7 +1914,7 @@ added: v5.7.0
 added: v0.7.0
 -->
 
-* Type: {number} **Default:** `2000`
+* Type: {number} **Default:** `1000`
 
 Limits maximum incoming headers count. If set to 0, no limit will be applied.