chore: Update to .NET 8 SDK #123

	# Copyright 2025 Google LLC
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.
	# Github action job to test core java library features on
	# downstream client libraries before they are released.
	on:
	push:
	branches:
	- main
	pull_request:
	paths:
	- '[Bb]ig[Tt]able'
	name: bigtable-conformance
	jobs:
	conformance:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	with:
	submodules: true
	- uses: actions/checkout@v4
	with:
	repository: googleapis/cloud-bigtable-clients-test
	ref: main
	path: cloud-bigtable-clients-test
	- uses: actions/setup-dotnet@v4
	with:
	dotnet-version: \|
	6.0.x
	8.0.x
	- uses: actions/setup-go@v5
	with:
	go-version: '>=1.20.2'
	- run: dotnet --version
	- run: go version
	- run: bash apis/Google.Cloud.Bigtable.V2/Google.Cloud.Bigtable.V2.ConformanceTests/bigtable-conformance.sh

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