Roll flutter/packages SHA (#463)

Rolls the flutter/packages SHA for tests to pick up
flutter/packages#9590

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Author: harryterkelsen

registry/flutter_packages.test

@@ -9,7 +9,7 @@ contact=ian@hixie.ch
 update=packages/rfw
 
 fetch=git -c core.longPaths=true clone https://github.com/flutter/packages.git tests
-fetch=git -c core.longPaths=true -C tests checkout 3890ceef72e140bc30cdeca59e0c70721f476fba
+fetch=git -c core.longPaths=true -C tests checkout 7018bc8eec241f8a2607486a5f6852a070f6e0a4
 test.windows=set USE_FLUTTER_TEST_FONT=1
 test.windows=.\customer_testing.bat
 test.posix=env USE_FLUTTER_TEST_FONT=1 ./customer_testing.sh