[Resource Tag][Step1] Support setting tags for BE nodes, and support create table with specified tags

[morningman]

Proposed changes

Step 1 of #5902
This CL mainly changes:

1. Support setting tags for BE nodes:

   alter system add backend "1272:9050, 1212:9050" properties("tag.location": "zoneA");
   alter system modify backend "1272:9050, 1212:9050" set ("tag.location": "zoneB");
   

   And for compatibility, all BE nodes will be set a "default" tag: "tag.location": "default".

2. Create a new class ReplicaAllocation to replace the previous replication_num.

   ReplicaAllocation represents the allocation of the replicas of a tablet. It contains a map from
   Tag to number of replicas.
   For example, if user set a table's replication num to 3, it will be converted to a ReplicaAllocation
   like: "tag.location.default" : "3", which means the tablet will have 3 replicas and all of them will be
   allocated in BE nodes with tag "default";

3. Support create table with replication allocation:

   CREATE TABLE example_db.table_hash
   (
   k1 TINYINT
   )
   DISTRIBUTED BY HASH(k1) BUCKETS 32
   PROPERTIES (
       "replication_allocation"="tag.location.zone1:1, tag.location.zone1:2"
   );
   

   Also support set replica allocation for dynamic tables, and modify replica allocation at runtime.

   For compatibility, user can still set "replication_num" = "3", and it will be automatically converted to:
   "tag.location.default" = "3".

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
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• Code refactor (Modify the code structure, format the code, etc...)

Checklist

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• I have created an issue on (Fix #ISSUE) and described the bug/feature there in detail
• Compiling and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
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Further comments

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[morningman]

This PR is covered by #6203