test1903: test use of COOKIEFILE - reset - COOKIEFILE

This also tests for the memory leak bug fixed by parent commit b559ef6f.

Ref: #10694

Closes https://github.com/curl/curl/pull/10712

tests/data/Makefile.inc

@@ -219,7 +219,7 @@ test1700 test1701 test1702 test1703 \
 \
 test1800 test1801 \
 \
-                                    test1904 test1905 test1906 test1907 \
+                           test1903 test1904 test1905 test1906 test1907 \
 test1908 test1909 test1910 test1911 test1912 test1913 test1914 test1915 \
 test1916 test1917 test1918 test1919 \
 \

tests/data/test1903

@@ -0,0 +1,51 @@
+<testcase>
+<info>
+<keywords>
+HTTP
+cookies
+CURLOPT_COOKIEFILE
+</keywords>
+</info>
+
+# Server-side
+<reply>
+<data nocheck="yes" crlf="yes">
+HTTP/1.1 200 OK
+Date: Tue, 09 Nov 2010 14:49:00 GMT
+Server: test-server/fake
+Content-Type: text/html
+Funny-head: yesyes swsclose
+Set-Cookie: foobar=name;
+Set-Cookie: secondcookie=present;
+
+</data>
+</reply>
+
+# Client-side
+<client>
+<server>
+http
+</server>
+ <name>
+CURLOPT_COOKIEFILE then reset then set again
+ </name>
+<tool>
+lib%TESTNUMBER
+</tool>
+<command>
+http://%HOSTIP:%HTTPPORT/we/want/%TESTNUMBER
+</command>
+<file name="log/cookies%TESTNUMBER" mode="text">
+# Netscape HTTP Cookie File
+# https://curl.se/docs/http-cookies.html
+# This file was generated by libcurl! Edit at your own risk.
+
+%HOSTIP	FALSE	/we/want/	FALSE	0	secondcookie	present
+%HOSTIP	FALSE	/we/want/	FALSE	0	foobar	name
+</file>
+</client>
+
+# Verify data after the test has been "shot"
+<verify>
+</verify>
+</testcase>