Update dependency org.testcontainers:testcontainers to v1.21.3

[xdev-renovate]

This PR contains the following updates:

Package	Type	Update	Change
org.testcontainers:testcontainers (source)	test	patch	1.21.0 -> 1.21.3
org.testcontainers:testcontainers (source)	compile	patch	1.21.0 -> 1.21.3

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Release Notes

testcontainers/testcontainers-java (org.testcontainers:testcontainers)

v1.21.3

Compare Source

What's Changed

• Update testcontainers/sshd version to 1.3.0 (#​10377) @​eddumelendez
• Support docker/mcp-gateway image (#​10378) @​eddumelendez
• Update testcontainers version to 1.21.2 (#​10369) @​github-actions
• Update docs version to 1.21.2 (#​10368) @​github-actions

v1.21.2

Compare Source

What's Changed

• Update ryuk version to 0.12.0 (#​10357) @​eddumelendez
• Update docs version to 1.21.1 (#​10281) @​github-actions
• Update testcontainers version to 1.21.1 (#​10282) @​github-actions

📖 Documentation

• Add DockerMcpGatewayContainer (#​10364) @​eddumelendez

📦 Dependency updates

• Update Gradle Wrapper from undefined to 8.14.2 (#​10352) @​github-actions

v1.21.1

Compare Source

What's Changed

• Update docs version to 1.21.0 (#​10193) @​github-actions
• Update testcontainers version to 1.21.0 (#​10194) @​github-actions

🚀 Features & Enhancements

• Expose Loki in LgtmContainer (#​10256) @​jaydeluca
• Add support to pull model for DockerModelRunnerContainer (#​10253) @​eddumelendez

🐛 Bug Fixes

• Use generic init script filename when copying it into a Cassandra container (#​9606) @​maximevw

📖 Documentation

• Add support to clickhouse JDBC V2 (#​10280) @​thiagohora
• Fix register listener for kafka docs (#​10268) @​julianladisch

📦 Dependency updates

• Update checkstyle version to 10.23.0 (#​10196) @​eddumelendez

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