[Enhancement] Add datacache memory tracker to trace the datacache memory usage. (backport #38884)

[mergify]

This is an automatic backport of pull request #38884 done by Mergify.
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Changes to be committed:
	modified:   be/src/block_cache/block_cache.cpp
	modified:   be/src/common/daemon.cpp
	modified:   be/src/http/default_path_handlers.cpp
	modified:   be/src/runtime/exec_env.h
	modified:   be/src/util/system_metrics.cpp
	modified:   be/src/util/system_metrics.h

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	both modified:   be/src/block_cache/block_cache.h
	deleted by us:   be/src/http/action/memory_metrics_action.cpp
	both modified:   be/src/runtime/exec_env.cpp
	both modified:   be/src/script/script.cpp

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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Why I'm doing: The datacache memory usage is unobservable, which brings difficulties to analyze process memory details.

What I'm doing:
Add datacache memory tracker to trace the datacache memory usage.
You can observe the datacache memory usage by follow urls:

http://${BE_HOST}:${BE_WEBSERVER_PORT}/mem_tracker
http://${BE_HOST}:${BE_WEBSERVER_PORT}/metrics
http://${BE_HOST}:${BE_WEBSERVER_PORT}/metrics/memory

What type of PR is this:

• BugFix
• Feature
• Enhancement
• Refactor
• UT
• Doc
• Tool

Does this PR entail a change in behavior?

• Yes, this PR will result in a change in behavior.
• No, this PR will not result in a change in behavior.

If yes, please specify the type of change:

• Interface/UI changes: syntax, type conversion, expression evaluation, display information
• Parameter changes: default values, similar parameters but with different default values
• Policy changes: use new policy to replace old one, functionality automatically enabled
• Feature removed
• Miscellaneous: upgrade & downgrade compatibility, etc.

Checklist:

• I have added test cases for my bug fix or my new feature
• This pr needs user documentation (for new or modified features or behaviors)
  • I have added documentation for my new feature or new function
• This is a backport pr

[mergify]

@mergify[bot]: Backport conflict, please reslove the conflict and resubmit the pr