gh-39111: build/pkgs/planarity/spkg-configure.m4: update header check #208

Job	Run time
test-new	15m 34s
test-mod (sagemath_categories-check)	8m 52s
test-long (src/sage/[a-f]*)	43m 1s
test-long (src/sage/[g-o]*)	38m 33s
test-long (src/sage/[p-z]*)	49m 31s
test-long (src/doc src/sage_docbuild src/sage_setup)	11m 51s
coverage-report	25m 54s
	3h 13m 16s

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