[Doc][Misc] Comprehensive documentation cleanup and grammatical fixes (#8073)

What this PR does / why we need it?
This pull request performs a comprehensive cleanup of the vLLM Ascend
documentation. It fixes numerous typos, grammatical errors, and phrasing
issues across community guidelines, developer documents, hardware
tutorials, and feature guides. Key improvements include correcting
hardware names (e.g., Atlas 300I), fixing broken links, cleaning up code
examples (removing duplicate flags and trailing commas), and improving
the clarity of technical explanations. These changes are necessary to
ensure the documentation is professional, accurate, and easy for users
to follow.

Does this PR introduce any user-facing change?
No, this PR contains documentation-only updates.

How was this patch tested?
The changes were manually reviewed for accuracy and grammatical
correctness. No functional code changes were introduced.

---------

Signed-off-by: herizhen <1270637059@qq.com>
Signed-off-by: herizhen <59841270+herizhen@users.noreply.github.com>

docs/source/developer_guide/contribution/testing.md

@@ -153,8 +153,8 @@ pip install -r requirements-dev.txt
 There are several principles to follow when writing unit tests:
 
 - The test file path should be consistent with the source file and start with the `test_` prefix, such as: `vllm_ascend/worker/worker.py` --> `tests/ut/worker/test_worker.py`
-- The vLLM Ascend test uses unittest framework. See [here](https://docs.python.org/3/library/unittest.html#module-unittest) to understand how to write unit tests.
-- All unit tests can be run on CPUs, so you must mock the device-related function to host.
+- The vLLM Ascend test uses unittest framework. See [the Python unittest documentation](https://docs.python.org/3/library/unittest.html#module-unittest) to understand how to write unit tests.
+- All unit tests can be run on CPUs, so you must mock the device-related functions on the host.
 - Example: [tests/ut/test_ascend_config.py](https://github.com/vllm-project/vllm-ascend/blob/main/tests/ut/test_ascend_config.py).
 - You can run the unit tests using `pytest`:
 
@@ -205,8 +205,8 @@ pytest -sv tests/ut/test_ascend_config.py
 
 ### E2E test
 
-Although vllm-ascend CI provides the [E2E test](https://github.com/vllm-project/vllm-ascend/blob/main/.github/workflows/vllm_ascend_test.yaml) on Ascend CI, you can run it
-locally.
+Although vllm-ascend CI provides E2E tests on Ascend CI (for example,
+[schedule_nightly_test_a2.yaml](https://github.com/vllm-project/vllm-ascend/blob/main/.github/workflows/schedule_nightly_test_a2.yaml), [schedule_nightly_test_a3.yaml](https://github.com/vllm-project/vllm-ascend/blob/main/.github/workflows/schedule_nightly_test_a3.yaml), [pr_test_full.yaml](https://github.com/vllm-project/vllm-ascend/blob/main/.github/workflows/pr_test_full.yaml)), you can run them locally.
 
 :::::{tab-set}
 :sync-group: e2e