fixup! Add missing specs for observer #403

Job	Run time
Event File	3s
Build Erlang/OTP (64-bit)	17m 33s
Build Erlang/OTP (macOS)	8m 0s
Build Erlang/OTP (iOS)	7m 16s
Build Erlang/OTP (Windows)	21m 19s
Build Erlang/OTP (32-bit)	8m 36s
Build and check documentation	8m 35s
Build Erlang/OTP (cross-compile)	14m 2s
Build Erlang/OTP (Types and Flavors)	8m 47s
Run static analysis	6m 48s
Build Erlang/OTP (clang)	5m 41s
Test Erlang/OTP (emulator)	45m 36s
Test Erlang/OTP (debug)	4m 53s
Test Erlang/OTP (asn1)	14m 50s
Test Erlang/OTP (common_test)	1h 26m 58s
Test Erlang/OTP (compiler)	10m 3s
Test Erlang/OTP (crypto)	5m 16s
Test Erlang/OTP (debugger)	4m 16s
Test Erlang/OTP (dialyzer)	18m 17s
Test Erlang/OTP (diameter)	11m 42s
Test Erlang/OTP (edoc)	3m 15s
Test Erlang/OTP (eldap)	3m 21s
Test Erlang/OTP (erl_docgen)	3m 25s
Test Erlang/OTP (erl_interface)	5m 59s
Test Erlang/OTP (et)	3m 21s
Test Erlang/OTP (eunit)	3m 37s
Test Erlang/OTP (ftp)	4m 20s
Test Erlang/OTP (inets)	9m 39s
Test Erlang/OTP (kernel)	1h 1m 4s
Test Erlang/OTP (megaco)	31m 33s
Test Erlang/OTP (mnesia)	19m 20s
Test Erlang/OTP (observer)	13m 35s
Test Erlang/OTP (os_mon)	3m 47s
Test Erlang/OTP (public_key)	4m 33s
Test Erlang/OTP (runtime_tools)	4m 24s
Test Erlang/OTP (ssh)	17m 59s
Test Erlang/OTP (ssl)	47m 18s
Test Erlang/OTP (stdlib)	35m 5s
Test Erlang/OTP (tftp)	5m 0s
Test Erlang/OTP (wx)	3m 57s
Test Erlang/OTP (xmerl)	6m 54s
Release Erlang/OTP	0s
Test Erlang/OTP (system)	17m 18s
	10h 17m 15s

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