[9.20] fix: doc: Use archived version of draft-icann-dnssec-keymgmt-01.txt

The iana.org link is gone.

Backport of MR !10010

Merge branch 'backport-mnowak/linkcheck-fix-draft-icann-dnssec-keymgmt-01.txt-link-9.20' into 'bind-9.20'

See merge request isc-projects/bind9!10011

doc/changelog/changelog-9.20.2.rst

@@ -25,7 +25,7 @@ New Features
   are loaded from the currently active bundle from the imported SKR.
 
   The implementation is loosely based on:
-  https://www.iana.org/dnssec/archive/files/draft-icann-dnssec-keymgmt-01.txt
+  https://web.archive.org/web/20250121040252/https://www.iana.org/dnssec/archive/files/draft-icann-dnssec-keymgmt-01.txt
   :gl:`#1128` :gl:`!9119`
 
 - Print the full path of the working directory in startup log messages.

doc/notes/notes-9.20.2.rst

@@ -27,7 +27,7 @@ New Features
 
   The implementation is loosely based on
   `draft-icann-dnssec-keymgmt-01.txt
-  <https://www.iana.org/dnssec/archive/files/draft-icann-dnssec-keymgmt-01.txt>`_.
+  <https://web.archive.org/web/20250121040252/https://www.iana.org/dnssec/archive/files/draft-icann-dnssec-keymgmt-01.txt>`_.
   :gl:`#1128`
 
 - Print the full path of the working directory in startup log messages.

lib/dns/include/dns/skr.h

@@ -18,7 +18,7 @@
  * A skr is a convenience type representing a Signed Key Response (SKR),
  * determining which DNSKEY, CDS, CDNSKEY and corresponding signatures
  * should be published at a given time. It is based on terminology used in
- * https://www.iana.org/dnssec/archive/files/draft-icann-dnssec-keymgmt-01.txt
+ * https://web.archive.org/web/20250121040252/https://www.iana.org/dnssec/archive/files/draft-icann-dnssec-keymgmt-01.txt
  */
 
 #include <isc/stdtime.h>