tests: add the "--resolve" keyword to tests that lack it

... even though they use the curl option "--resolve".

This makes it more convenient to choose or skip the tests.

For example Privoxy's cts test framework relies on the "--resolve"
keyword when executing the "upstream-tests" scenario to skip curl
tests that aren't expected to work when the requests are made through
Privoxy. While some of the modified tests are already skipped for
other reasons through other means when testing Privoxy, it's good to
be consistent.

Closes #21930

tests/data/test1629

@@ -4,6 +4,7 @@
 <keywords>
 HTTP
 HTTP GET
+--resolve
 </keywords>
 </info>
 

tests/data/test1645

@@ -6,6 +6,7 @@ HTTP
 HTTP GET
 cookies
 cookiejar
+--resolve
 </keywords>
 </info>
 # Server-side

tests/data/test1646

@@ -3,6 +3,7 @@
 <info>
 <keywords>
 netrc
+--resolve
 </keywords>
 </info>
 

tests/data/test1966

@@ -5,6 +5,7 @@
 HTTP
 HTTP GET
 HTTP Digest auth
+--resolve
 </keywords>
 </info>
 # Server-side

tests/data/test2008

@@ -5,6 +5,7 @@
 HTTP
 -G
 --proto-default
+--resolve
 </keywords>
 </info>
 

tests/data/test2500

@@ -5,6 +5,7 @@
 HTTP
 HTTP GET
 HTTP/3
+--resolve
 </keywords>
 </info>
 

tests/data/test2503

@@ -5,6 +5,7 @@
 HTTP
 HTTP/3
 HTTPS
+--resolve
 -w
 %header
 </keywords>

tests/data/test31

@@ -6,6 +6,7 @@ HTTP
 HTTP GET
 cookies
 cookiejar
+--resolve
 </keywords>
 </info>
 # Server-side

tests/data/test779

@@ -6,6 +6,7 @@ HTTP
 IMAP
 oauth2-bearer
 followlocation
+--resolve
 </keywords>
 </info>
 # Server-side

tests/data/test795

@@ -5,6 +5,7 @@
 HTTP
 IMAP
 followlocation
+--resolve
 </keywords>
 </info>
 # Server-side