Simplify the version bump process. ### Description

Simplify the version bump process.

- Use substitution hook in docs to update CDN URL.
  - In `dev` or `prerelease` versions, it will point to `dev` url
  - In `stable` versions, it will point it `vX.Y.Z` url
- Introduce a version bump script `tools/bump_version.py`.


~- Use `bump2version` to bump Python versions (continuing from #2460)~
~- Use `npm version` to bump JS versions~
~- Update `run_docker` script to use latest deployed pre-built docker image when `--pre-built` option is specified.~

### Checklists

- [x] Add new / update outdated documentation

package:
  name: pandas
  version: 1.4.2
source:
  url: https://files.pythonhosted.org/packages/5a/ac/b3b9aa2318de52e40c26ae7b9ce6d4e9d1bcdaf5da0899a691642117cf60/pandas-1.4.2.tar.gz
  sha256: 92bc1fc585f1463ca827b45535957815b7deb218c549b7c18402c322c7549a12
  patches:
    - patches/fix_json_signature.patch
build:
  cflags:
    -Werror=implicit-function-declaration -Werror=mismatched-parameter-types
    -Werror=mismatched-return-types -Oz
  ldflags: --Wl,--fatal-warnings -Oz
requirements:
  run:
    - distutils
    - numpy
    - python-dateutil
    - pytz
    - setuptools
test:
  imports:
    - pandas

package:
  name: pandas
  version: 1.4.2
source:
  url: https://files.pythonhosted.org/packages/5a/ac/b3b9aa2318de52e40c26ae7b9ce6d4e9d1bcdaf5da0899a691642117cf60/pandas-1.4.2.tar.gz
  sha256: 92bc1fc585f1463ca827b45535957815b7deb218c549b7c18402c322c7549a12
  patches:
    - patches/fix_json_signature.patch
build:
  cflags:
    -Werror=implicit-function-declaration -Werror=mismatched-parameter-types
    -Werror=mismatched-return-types -Oz
  ldflags: --Wl,--fatal-warnings -Oz
requirements:
  run:
    - distutils
    - numpy
    - python-dateutil
    - pytz
    - setuptools
test:
  imports:
    - pandas
