Update all versions to 0.4.0 #3287

Job	Run time
format	1m 38s
lint	1m 31s
check-proto-changes-python	1m 38s
codecov (./packages/autogen-core)	1m 54s
docs (./packages/autogen-core)	2m 43s
docs-example-check (./packages/autogen-core)	3m 14s
codecov (./packages/autogen-magentic-one)	4m 59s
markdown-code-lint	3m 1s
codecov (./packages/autogen-ext)	5m 22s
codecov (./packages/autogen-agentchat)	2m 2s
mypy (./packages/autogen-core)	2m 59s
pyright (./packages/autogen-core)	1m 55s
mypy (./packages/autogen-magentic-one)	1m 58s
pyright (./packages/autogen-magentic-one)	1m 49s
samples-code-check	1m 51s
mypy (./packages/agbench)	1m 45s
test (./packages/autogen-core)	1m 38s
pyright (./packages/agbench)	1m 37s
mypy (./packages/autogen-ext)	2m 35s
test (./packages/autogen-magentic-one)	2m 2s
pyright (./packages/autogen-ext)	2m 0s
mypy (./packages/autogen-agentchat)	1m 49s
pyright (./packages/autogen-agentchat)	2m 0s
test (./packages/autogen-ext)	3m 40s
mypy (./packages/magentic-one-cli)	1m 40s
pyright (./packages/magentic-one-cli)	1m 45s
test (./packages/autogen-agentchat)	1m 46s
	1h 2m 51s

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