hostlist: add hostlist_find_hostname and support #223

Job	Run time
spelling	6s
validate commits	0s
Generate build matrix	6s
python linting	30s
bookworm - test-install	1m 25s
bookworm - 32 bit	1m 31s
noble - test-install	1m 55s
el9 - test-install	1m 34s
alpine - test-install	1m 11s
fedora40 - test-install	1m 22s
jammy - test-install	1m 25s
focal - py3.8	1m 29s
bookworm - gcc-12,content-s3,distcheck	1m 51s
fedora40 - clang-18	1m 22s
coverage	1m 38s
el8 - ascii	1m 36s
el8 - system,coverage	1m 39s
inception	1m 21s
flux-pam check	1m 28s
flux-sched check	1m 26s
flux-accounting check	1m 28s
flux-pmix check	1m 25s
Generate docker manifest	0s
	27m 48s

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