Fixed replacing match values only when a test succeeds.

TODO

src/lib-sieve/mcht-matches.c

src/lib-sieve/plugins/include/ext-include-common.c

src/lib-sieve/plugins/regex/mcht-regex.c

src/lib-sieve/sieve-match-types.c

src/lib-sieve/sieve-match-types.h

tests/extensions/variables/match.svtest

tests/match-types/matches.svtest