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Update MIGRATION_FROM_3_x.md #84

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Job	Run time
source_abi	1m 10s
abi_linux_build (unversioned)	4m 27s
abi_linux_build (4_2_5)	4m 35s
build_windows (unversioned)	18m 55s
build_macos_x86_64 (unversioned)	8m 10s
abi_linux_build (4_2_6)	4m 19s
build_windows (4_2_5)	19m 47s
build_macos_x86_64 (4_2_5)	6m 17s
build_windows (4_2_6)	19m 7s
build_macos_x86_64 (4_2_6)	6m 19s
abi_linux_x86_64_test	36s
macos_x86_64_test	2m 52s
mock_windows	1m 17s
	1h 37m 51s