doc: tweak Captures documentation
#2040
BurntSushici.yml
on: push
msrv
2m 27s
testfull-regex
4m 22s
testfull-regex-automata
8m 47s
testfull-regex-syntax
1m 53s
testfull-regex-capi
22s
miri-regex-automata
7m 57s
rustfmt
12s
Matrix: test