Support to get the metric data from a prometheus metric api with basic auth enabled

[zhifanggao]

support to get the metrics data from prometheus metric api with basic auth enabled

the configmap of volcano-scheduler can be like this:

actions: "enqueue, allocate, backfill"
tiers:
- plugins:
  - name: priority
  - name: conformance
  - name: usage
    enablePredicate: false
    arguments:
      usage.weight: 50
      cpu.weight: 1
      memory.weight: 1
      thresholds:
        cpu: 80
        mem: 70
- plugins:
  - name: overcommit
  - name: drf
    enablePreemptable: false
  - name: predicates
  - name: proportion
  - name: nodeorder
  - name: binpack
  - name: gang
metrics:
  type: prometheus
  address: http://xxx:9090/
  basicauth: true
  username: yy
  password: zz
  interval: 30s

[Monokaix]

Hi，can you also update the usage design doc first？

[lowang-bh]

relative PR #2961

[zhifanggao]

relative PR #2961

👍, I will check the PR.

[volcano-sh-bot]

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[zhifanggao]

Hi，can you also update the usage design doc first？

changed