Fix typos in installation.md

[vi3itor]

trafficstars

Motivation

Fix a few typos to make it clear for those who is reading it for the first time.

Modification

Several typos, such as incorrect tense (e.g., "If you prefer other versions, just modified the Dockerfile").

BC-breaking (Optional)

No

Use cases (Optional)

Checklist

Before PR:

• [x] I have read and followed the workflow indicated in the CONTRIBUTING.md to create this PR.
• [x] Pre-commit or linting tools indicated in CONTRIBUTING.md are used to fix the potential lint issues. Not relevant:
• [ ] Bug fixes are covered by unit tests, the case that causes the bug should be added in the unit tests.
• [ ] New functionalities are covered by complete unit tests. If not, please add more unit tests to ensure correctness.
• [ ] The documentation has been modified accordingly, including docstring or example tutorials.

After PR:

• [x] CLA has been signed and all committers have signed the CLA in this PR.

[CLAassistant]

All committers have signed the CLA.