Add ANGLE's DEPS to trybot exclusions.

This should force DEPS changes in ANGLE to trigger all trybots.
ANGLE's bot config is a bit special since we use recursive DEPS.

Bug: 850100
Bug: 899737
Change-Id: Iab6e996663386f66f1fa05f2ee10531d6bd85224
Reviewed-on: https://chromium-review.googlesource.com/c/1307734
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#604005}

testing/buildbot/trybot_analyze_config.json

@@ -53,6 +53,7 @@
       "net/data/.*",
       "sql/test/data/.*",
       "third_party/accessibility-audit/axs_testing.js",
+      "third_party/angle/DEPS",
       "third_party/chaijs/.*(css|html|js)",
       "third_party/closure_compiler/.*(css|html|js)",
       "third_party/hunspell_dictionaries/.*",