GKE A3 Mega and High are not experimental #3465

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@ighosh98

The following contributors were found for this pull request:

✅ 98f2e54 Author: @ighosh98 <indr*******osh@google.com>
✅ 0ea8282 Author: @dgouju <dgouju@users.noreply.github.com>
✅ dd8d692 Author: @SwarnaBharathiMantena <swarn**********1208@gmail.com>, <sw****bm@google.com>
✅ 77322a5 Author: @annuay-google <an***y@google.com>
✅ 8e28be6 Author: @mr0re1 <o***v@google.com>
✅ fe88514 Author: @mohitchaurasia91 <mohi*******sia@google.com>
✅ e100f57 Author: @ankitkinra <1037624+ankitkinra@users.noreply.github.com>
✅ 2933f6f Author: @harshthakkar01 <har******kar@google.com>
✅ 31195d0 Author: @RachaelSTamakloe <rt*****oe@google.com>, <63983467+RachaelSTamakloe@users.noreply.github.com>
✅ 422aebf Author: @abbas1902 <abb******med@google.com>, <ab*****02@hotmail.ca>, <69826914+abbas1902@users.noreply.github.com>
✅ 51ef267 Author: @nick-stroud <nic*****ud@google.com>
✅ 5ce784f Author: @parulbajaj01 <par*****aj@google.com>
✅ 3339f2b Author: @chajath <ch****h@gmail.com>
✅ 6bd418d Author: @samskillman <sam******an@google.com>
✅ d76cfe2 Author: @wiktorn <wi****n@google.com>

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