Update azurerm_synapse_spark_pool to support spark 3.1 instead of 3.0

[oguzkilcan]

Azure Synapse now support Apache Spark 3.1 (preview) and support for Spark 3.0 is dropped.

❯ make acctests SERVICE='synapse' TESTARGS='-run=TestAccSynapseSpark3Pool_'
==> Checking that code complies with gofmt requirements...
==> Checking that Custom Timeouts are used...
==> Checking that acceptance test packages are used...
TF_ACC=1 go test -v ./internal/services/synapse -run=TestAccSynapseSpark3Pool_ -timeout 180m -ldflags="-X=github.com/hashicorp/terraform-provider-azurerm/version.ProviderVersion=acc"
=== RUN   TestAccSynapseSpark3Pool_complete
=== PAUSE TestAccSynapseSpark3Pool_complete
=== RUN   TestAccSynapseSpark3Pool_update
=== PAUSE TestAccSynapseSpark3Pool_update
=== CONT  TestAccSynapseSpark3Pool_complete
=== CONT  TestAccSynapseSpark3Pool_update
--- PASS: TestAccSynapseSpark3Pool_complete (1517.20s)
--- PASS: TestAccSynapseSpark3Pool_update (1574.70s)
PASS
ok      github.com/hashicorp/terraform-provider-azurerm/internal/services/synapse       1576.160s

[katbyte]

Thanks @oguzkilcan - overall looks good but we need to keep the old value around lest we break someones config (even if the API stopped working for old values) - we'll remove it in 3.0

[github-actions]

This functionality has been released in v2.75.0 of the Terraform Provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!

[github-actions]

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