Fix errors in README.md

[Rauf00]

Signed-off-by: Rauf Shimarov 55862995+Rauf00@users.noreply.github.com

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• What does this PR aim to accomplish?:
  The README.md contains some grammatical errors and can be made more concise.

• How does this PR accomplish the above?:
  a. Line 19, it might be not clear to which “process” the sentence is referring. Also, make it explicit that it is the installation process that “takes less than ten minutes”, not the installer itself
  b. Line 23, 133, “command line” is missing a hyphen
  c. Line 61, the sentence is too long and should be split into two to have better readability
  d. Line 71, “open source” is missing a hyphen
  e. Line 135, a wrong preposition “of” is used

• What documentation changes (if any) are needed to support this PR?:
  The documentation needs to be changed according to the suggested corrections described above

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