docs: Adds CHANGELOG entries detailing new and modified tests

Author: weierophinney

CHANGELOG.md

@@ -1 +1,12 @@
 # Change Log
+
+## Added
+
+- Adds `UriIntegrationTest::testGetPathNormalizesMultipleLeadingSlashesToSingleSlashToPreventXSS()`, `UriIntegrationTest::testStringRepresentationWithMultipleSlashes(array $test)`, and `RequestIntegrationTest::testGetRequestTargetInOriginFormNormalizesUriWithMultipleLeadingSlashesInPath()`.
+  These validate that a path containing multiple leading slashes is (a) represented with a single slash when calling `UriInterface::getPath()`, and (b) represented without changes when calling `UriInterface::__toString()`, including when calling `RequestInterface::getRequestTarget()` (which returns the path without the URI authority by default, to comply with origin-form).
+  This is done to validate mitigations for [CVE-2015-3257](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-3257).
+
+## Changed
+
+- Modifies `UriIntegrationTest::testPathWithMultipleSlashes()` to only validate multiple slashes in the middle of a path.
+  Multiple leading slashes are covered with the newly introduced tests.