fixed grammar and typos

[photonguava]

What did this PR accomplish?

• Fixed some obvious typos and grammar issues.
• Improved readability of some sentences.

[github-actions[bot]]

The following mistakes were identified:

/home/runner/work/wstg/wstg/document/4-Web_Application_Security_Testing/10-Business_Logic_Testing/08-Test_Upload_of_Unexpected_File_Types.md 9:516 ✖ Incorrect usage of the term: “web site”, use “site” instead terminology 17:101 ✖ Incorrect usage of the term: “web site”, use “site” instead terminology 33:16 ✖ Incorrect usage of the term: “website”, use “site” instead terminology 34:16 ✖ Incorrect usage of the term: “website”, use “site” instead terminology 35:16 ✖ Incorrect usage of the term: “website”, use “site” instead terminology

[kingthorin]

Thanks. I understand you didn’t cause the terminology issues but if you could fix them too, that’d really help.

[kingthorin]

Thanks