Temporary add b/149317789 to bugmap

On taimen/walley DeviceBootTest.SELinuxUncheckedDenialBootTest
occasionally fails with following selinux denials:

02-10 10:21:23.940   784   784 I auditd  : type=1400 audit(0.0:4): avc: denied { getattr } for comm="apexd" path="/metadata/apex/sessions" dev="sde41" ino=17 scontext=u:r:apexd:s0 tcontext=u:object_r:metadata_file:s0 tclass=dir permissive=0
02-10 10:21:23.943   784   784 I auditd  : type=1400 audit(0.0:5): avc: denied { read } for comm="apexd" name="sessions" dev="sde41" ino=17 scontext=u:r:apexd:s0 tcontext=u:object_r:metadata_file:s0 tclass=dir permissive=0
02-10 10:21:24.577   784   784 I auditd  : type=1400 audit(0.0:7): avc: denied { read } for comm="apexd" name="sessions" dev="sde41" ino=17 scontext=u:r:apexd:s0 tcontext=u:object_r:metadata_file:s0 tclass=dir permissive=0

Since the behaviour is flakey, temporary ignore these denials to deflake
presubmit.

Test: builds
Bug: 149317789
Change-Id: Iff3295d2a9be8cf0029a2e5867ebd231badfc9e8
diff --git a/sepolicy/vendor/bug_map b/sepolicy/vendor/bug_map
index 6c304cf..a13d7e2 100644
--- a/sepolicy/vendor/bug_map
+++ b/sepolicy/vendor/bug_map
@@ -1,3 +1,4 @@
+apexd metadata_file dir b/149317789
 bootanim vendor_default_prop file b/79617173
 drmserver app_data_file dir b/77869200
 drmserver sdcardfs dir b/77869200