Removed incorrect line from contact form docs.

From disqus comments.
Update docs/en/tutorials/1-building-a-basic-site.md

Fixed typo in code block. UL tag was opening instead of closing.
Merge pull request #1084 from jcwacky/patch-1

Update docs/en/tutorials/1-building-a-basic-site.md
Setting SapphireTest::is_running_test() in PHPUnit bootstrap

Otherwise conditional logic will only succeed
when run through "sake dev/tests", not when
run through phpunit directly (which is the recommended way now)
BUGFIX: for date manipulation use the SS_Datetime::now, otherwise it does not respect the mock date.
NEW: Allow configuration of send_all_emails_to, ccs_all_emails_to, and bcc_all_emails_to via the config system.
NEW: Added Email::send_all_emails_from() setting.
FIX: Set up the test mailer before loading the fixture, in case fixture-creation causes emails to be generated.
FIX: Fixed operation of inlined images in Mailer, when no inlined images actually attached.
API CHANGE: Added Security::set_login_url() so that you can define an alternative log-in page if you have made one yourself.
BUGFIX: Improved detection of empty HTMLText fields.
FIX: Removed notice-level error after forms w/ required fields are made readonly.
FIX: Added error message fields to default search form
MINOR: Fixed a glitch that causes warnings in cli-script execution.
BUGFIX: Prevent notice-level error in Session code when non-array is turned into an array.
BUGFIX: Better error message when 401 response is corrupted.
BUGFIX: Updated SilverStripe error handler so that log_errors still works.
MINOR: Minor fixes to FunctionalTest
MINOR: Don't throw redirection warning if redirection to the same place.
BUGFIX: Made CSRF-error wording friendlier.