t/lib-git-svn.sh: check GIT_TEST_SVN_HTTPD when running SVN HTTP tests
Once upon a time the GIT_SVN_TEST_HTTPD environment variable needed to be set to enable SVN HTTP tests [1]. Then 3b072c577b (tests: replace test_tristate with "git env--helper", 2019-06-21) came along, and attempted to turn GIT_SVN_TEST_HTTPD into a bool, but while doing so it mistyped the variable name, and started to check GIT_TEST_HTTPD instead. Consequently, if someone explicitly set GIT_TEST_HTTPD to true and has only the general 'git-svn' dependencies installed but not the Subversion server modules for Apache (libapache2-mod-svn), then a couple of 'git-svn' tests fail, because they can't start httpd due to the missing module. We could simply fix this by checking the GIT_SVN_TEST_HTTPD variablewith 'git env--helper', but notice that the name of this variable doesn't conform to our usual GIT_TEST_* convention. So let's check the GIT_TEST_SVN_HTTPD instead. [1] a8a5d25118 (git svn: migrate tests to use lib-httpd, 2016-07-23) Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>