[docs] moved M1 instructions further up (ray-project#36438)

I've seen many folks miss the M1 instructions. Moved them up per @akshay-anyscale's good suggestion.

## Checks

- [x] I've signed off every commit(by using the -s flag, i.e., `git commit -s`) in this PR.
- [x] I've run `scripts/format.sh` to lint the changes in this PR.
- [x] I've included any doc changes needed for https://docs.ray.io/en/master/.
    - [ ] I've added any new APIs to the API Reference. For example, if I added a 
           method in Tune, I've added it in `doc/source/tune/api/` under the 
           corresponding `.rst` file.
- [ ] I've made sure the tests are passing. Note that there might be a few flaky tests, see the recent failures at https://flakey-tests.ray.io/
- Testing Strategy
   - [ ] Unit tests
   - [ ] Release tests
   - [ ] This PR is not tested :(

doc/source/ray-contribute/docs.ipynb

@@ -28,7 +28,22 @@
  "cd ray/doc\n",
  "```\n",
  "\n",
- "**Note**: If you are using Apple Silicon (M1), follow the instructions below before continuing.\n",
+ "## Building Docs for Apple Silicon (M1)\n",
+ "\n",
+ "Note: If you are not using Apple Silicon (M1), skip to the [next section](#install-dependencies).\n",
+ "\n",
+ "If you are using an Apple Silicon (M1) some of the dependencies required for building the docs don't have binary packages available by default (not available in PyPI). \n",
+ "\n",
+ "The simplest way to install those dependencies is with `conda` (https://docs.conda.io/en/latest/miniconda.html) first, that way `pip` won't try to install them by building them from scratch.\n",
+ "\n",
+ "To do that, make sure you create and/or activate the conda environment, and then install the dependencies with:\n",
+ "\n",
+ "\n",
+ "```shell\n",
+ "conda install -c conda-forge xgboost lightgbm\n",
+ "```\n",
+ "\n",
+ "## Install Dependencies\n",
  "\n",
  "Activate the Python environment you are using (e.g., venv, conda, etc.). Install the documentation dependencies, with the following command:\n",
  "\n",
@@ -62,21 +77,6 @@
  "For reproducing CI build failures locally, you might want to use `make html`, which\n",
  "is the same as `make develop` but treats warnings as errors.\n",
  "\n",
- "## Building Docs for Apple Silicon (M1)\n",
- "\n",
- "If you are using an Apple Silicon (M1) some of the dependencies required for building the docs don't have binary packages available by default (not available in PyPI).\n",
- "\n",
- "The simplest way to install those dependencies is with `conda` (https://docs.conda.io/en/latest/miniconda.html) first, that way `pip` won't try to install them by building them from scratch.\n",
- "\n",
- "To do that, make sure you create and/or activate the conda environment, and then install the dependencies with:\n",
- "\n",
- "\n",
- "```shell\n",
- "conda install -c conda-forge xgboost lightgbm\n",
- "```\n",
- "\n",
- "After that you can install the other dependencies as described above.\n",
- "\n",
  "## The basics of our build system\n",
  "\n",
  "The Ray documentation is built using the [`sphinx`](https://www.sphinx-doc.org/) build system.\n",
@@ -171,23 +171,15 @@
  {
  "cell_type": "code",
  "execution_count": null,
- "metadata": {
- "vscode": {
- "languageId": "python"
- }
- },
+ "metadata": {},
  "outputs": [],
  "source": []
  },
  {
  "cell_type": "code",
  "execution_count": null,
  "id": "ba88d95f",
- "metadata": {
- "vscode": {
- "languageId": "python"
- }
- },
+ "metadata": {},
  "outputs": [],
  "source": [
  "# __function_api_start__\n",
@@ -210,6 +202,7 @@
  ]
  },
  {
+ "attachments": {},
  "cell_type": "markdown",
  "id": "6971eeb0",
  "metadata": {},
@@ -318,10 +311,7 @@
  "metadata": {
  "tags": [
  "hide-cell"
- ],
- "vscode": {
- "languageId": "python"
- }
+ ]
  },
  "outputs": [],
  "source": [
@@ -383,11 +373,7 @@
  "cell_type": "code",
  "execution_count": null,
  "id": "8412103e",
- "metadata": {
- "vscode": {
- "languageId": "python"
- }
- },
+ "metadata": {},
  "outputs": [],
  "source": [
  "num_workers = 8\n",