Add test for checking mv projection clamping

This clip crashes on frame 67 if the projection is not clamped (ref: dav1d!1023 (merged)). Incorrect motion vector selections starting from frame 65 eventually leads to symbol overread on frame 67.

Concerns I have with merging this:

1. At least on my machine, this test takes 10s to run, which is significantly longer than every other test. For comparison, the rest of the tests take 60s total for my machine to run. I'm not sure how to fabricate a smaller test case with the same issue, but that would probably be more ideal.
2. This is a very short clip from a Japanese television show. I am not sure what is the policy regarding using test data sourced from copyrighted materials.

10-bit/mv/meson.build

+# Copyright © 2020, VideoLAN and dav1d authors
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# 1. Redistributions of source code must retain the above copyright notice, this
+#    list of conditions and the following disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright notice,
+#    this list of conditions and the following disclaimer in the documentation
+#    and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+tests += [
+	['mv_projection_clamp', files('mv_projection_clamp.ivf'), 'b29c4e3209e6e5ba0faaedfc898d2135'],
+]