"query resolution for a domain with a valid glueless delegation chain" check fails

Job #4669303 failed for 72e30c3c.

After !9284 (merged) got backported, the "checking query resolution for a domain with a valid glueless delegation chain" check of the resolver system test started failing frequently (tho not in 100% cases).

Got SERVFAIL is where NOERROR is expected:

; <<>> DiG 9.16.51-dev <<>> -p 11300 foo.bar.sub.tld1 @10.53.0.1 TXT
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 7241
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; COOKIE: 23b9e781eec3919a0100000066cbdeedd7d1110287323da9 (good)
;; QUESTION SECTION:
;foo.bar.sub.tld1.		IN	TXT

;; Query time: 40 msec
;; SERVER: 10.53.0.1#11300(10.53.0.1)
;; WHEN: Mon Aug 26 01:48:29 UTC 2024
;; MSG SIZE  rcvd: 73

It seems to be enough to bump max-recursion-queries in resolver/ns1/named.conf.in from 50 to 100.