Remove android_compile_rel on android tryserver from mb_config.pyl.

It's the same thing as linux_android_rel_ng without the tests.
Note that there's no test-less mirror of android_n5x_swarming_rel,
which is also on the CQ.

Need to remove it here before updating buildbucket.config

TBR=phajdan.jr@chromium.org

Bug: 773872
Change-Id: I7a04f92f19752ab3f31cd2203249f485fe678c94
Reviewed-on: https://chromium-review.googlesource.com/748216
Commit-Queue: Benjamin Pastene <bpastene@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#513223}

PRESUBMIT_test.py

@@ -504,7 +504,6 @@ class TryServerMasterTest(unittest.TestCase):
             'android_clang_dbg_recipe',
             'android_compile_dbg',
             'android_compile_mips_dbg',
-            'android_compile_rel',
             'android_compile_x64_dbg',
             'android_compile_x86_dbg',
             'android_coverage',

tools/mb/mb_config.pyl

@@ -539,7 +539,6 @@
       'android_clang_dbg_recipe': 'android_clang_asan_errorprone_findbugs_debug_trybot',
       'android_compile_dbg': 'android_debug_trybot',
       'android_compile_mips_dbg': 'android_debug_trybot_mipsel',
-      'android_compile_rel': 'android_release_trybot',
       'android_compile_x64_dbg': 'android_debug_trybot_x64',
       'android_compile_x86_dbg': 'android_debug_trybot_x86',
       'android_coverage': 'android_debug_trybot_java_coverage',