add semgrep ignore file #5386

Job	Run time
http3_test	52s
nginx (1.16.1)	1m 17s
android_ndk_lts (aarch64-linux-android)	1m 7s
docker	2m 0s
quiche	4m 37s
android_ndk_lts (armv7-linux-androideabi)	59s
quiche (boringssl-boring-crate)	4m 13s
quiche_ios (x86_64-apple-ios)	1m 13s
android_ndk_lts (x86_64-linux-android)	1m 0s
quiche (openssl)	7m 31s
quiche_ios (aarch64-apple-ios)	1m 8s
quiche_macos (macos-13)	3m 51s
android_ndk_lts (i686-linux-android)	1m 4s
quiche_macos (macos-latest)	1m 51s
quiche_multiarch (aarch64-unknown-linux-gnu)	2m 57s
quiche_windows (x86_64-pc-windows-msvc)	4m 31s
quiche_multiarch (armv7-unknown-linux-gnueabihf)	3m 15s
quiche_windows (i686-pc-windows-msvc)	4m 2s
quiche_multiarch (i686-unknown-linux-gnu)	1m 45s
quiche_windows (x86_64-pc-windows-gnu)	5m 54s
quiche_windows (i686-pc-windows-gnu)	6m 7s
	1h 1m 14s

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