Use o_stream_nsend*() to make sure write errors are caught.

src/lib-sieve-tool/sieve-tool.c

src/lib-sieve/cmd-redirect.c

src/lib-sieve/plugins/enotify/mailto/ntfy-mailto.c

src/lib-sieve/plugins/notify/cmd-notify.c

src/lib-sieve/plugins/vacation/cmd-vacation.c

src/lib-sieve/plugins/vnd.dovecot/report/cmd-report.c

src/lib-sieve/sieve-actions.c

src/lib-sieve/sieve-binary-dumper.c

src/lib-sieve/sieve-code-dumper.c

src/lib-sieve/sieve-result.c

src/lib-sieve/sieve.c

src/managesieve-login/managesieve-proxy.c

src/sieve-tools/sieve-filter.c

src/sieve-tools/sieve-test.c

src/testsuite/testsuite-result.c

src/testsuite/testsuite-smtp.c