Auto merge of #19875 - asajeffrey:test-perf-use-https-for-git-clone, r=jdm

Use https github URL to clone servo-warc-tests repo

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Fixes timeouts such as http://build.servo.org/builders/linux-nightly/builds/583/steps/test/logs/stdio caused by github.com not being in the ssh known hosts.

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- [X] These changes do not require tests because this is test infrastructure

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etc/ci/performance/test_perf.sh

@@ -26,8 +26,10 @@ else
     echo "Found existing test cases, skipping download and unzip."
 fi
 
+# We use the https URL for the repo so the clone works even if
+# github.com isn't in ssh's known hosts.
 WARC_DIR="./servo-warc-tests"
-WARC_REPO="git@github.com:servo/servo-warc-tests.git"
+WARC_REPO="https://github.com/servo/servo-warc-tests.git"
 
 # Clone the warc tests if they don't exist
 if [[ ! -d ${WARC_DIR} ]]; then