[release/2.1] Update blob upload to use managed identity (#22647)

[Abe27342]

Description

Updates the blob upload steps to use the pipeline's identity as authentication rather than a storage key.

Cherry-pick of #22647

[msfluid-bot]

Could not find a usable baseline build with search starting at CI 2bb28a0dbaadcd65d498ed4600f006657ea0809b

Generated by :no_entry_sign: dangerJS against 41cd0761f55c06ccde4f6f14c2af950ddea8967c

[microsoft-github-policy-service[bot]]

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