Update Fedora/Centos installation directions.
Update Fedora/Centos installation directions.

Fixes #6177.

Closes #6644.

PiperOrigin-RevId: 221118576

davidzchen/bazel,katre/bazel,katre/bazel,bazelbuild/bazel,katre/bazel,safarmer/bazel,bazelbuild/bazel,safarmer/bazel,cushon/bazel,ulfjack/bazel,ButterflyNetwork/bazel,dslomov/bazel,ButterflyNetwork/bazel,davidzchen/bazel,cushon/bazel,dslomov/bazel,safarmer/bazel,dslomov/bazel-windows,dslomov/bazel-windows,safarmer/bazel,meteorcloudy/bazel,meteorcloudy/bazel,aehlig/bazel,meteorcloudy/bazel,cushon/bazel,perezd/bazel,akira-baruah/bazel,katre/bazel,aehlig/bazel,perezd/bazel,werkt/bazel,ButterflyNetwork/bazel,katre/bazel,dslomov/bazel-windows,davidzchen/bazel,twitter-forks/bazel,twitter-forks/bazel,twitter-forks/bazel,meteorcloudy/bazel,aehlig/bazel,davidzchen/bazel,akira-baruah/bazel,cushon/bazel,meteorcloudy/bazel,twitter-forks/bazel,ulfjack/bazel,werkt/bazel,davidzchen/bazel,aehlig/bazel,dslomov/bazel,bazelbuild/bazel,dslomov/bazel-windows,cushon/bazel,akira-baruah/bazel,bazelbuild/bazel,katre/bazel,cushon/bazel,perezd/bazel,aehlig/bazel,dslomov/bazel,perezd/bazel,ButterflyNetwork/bazel,safarmer/bazel,dslomov/bazel-windows,werkt/bazel,akira-baruah/bazel,twitter-forks/bazel,davidzchen/bazel,werkt/bazel,ButterflyNetwork/bazel,ButterflyNetwork/bazel,akira-baruah/bazel,twitter-forks/bazel,meteorcloudy/bazel,perezd/bazel,bazelbuild/bazel,twitter-forks/bazel,dslomov/bazel,ulfjack/bazel,perezd/bazel,ulfjack/bazel,bazelbuild/bazel,safarmer/bazel,dslomov/bazel,davidzchen/bazel,aehlig/bazel,perezd/bazel,akira-baruah/bazel,werkt/bazel,dslomov/bazel-windows,ulfjack/bazel,ulfjack/bazel,meteorcloudy/bazel,dslomov/bazel,werkt/bazel,aehlig/bazel,ulfjack/bazel