Update testcontainer.version to v1.21.3

This MR contains the following updates:

Package	Type	Update	Change
org.testcontainers:postgresql (source)	test	patch	1.21.2 -> 1.21.3
org.testcontainers:junit-jupiter (source)	test	patch	1.21.2 -> 1.21.3

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Release Notes

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

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

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This MR has been generated by Renovate Bot.

added 15 commits

• 6bef298d...cc2467b8 - 14 commits from branch master
• e481dc64 - Update testcontainer.version to v1.21.3

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changed the description