Bug 1071661 - popd & pushd are bashim. Force the usage of bash instead r=bhearsum

From e9c608bddbe31ad8915179ca6600eecdf893064b Mon Sep 17 00:00:00 2001
 of sh
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 scripts/release/stage-tasks.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)