[Bugfix:System] Removed deprecated --no-suggest

[saumyaborwankar]

Please check if the PR fulfills these requirements:

• Tests for the changes have been added/updated (if possible)
• Documentation has been updated/added if relevant

What is the current behavior?

There was a warning message:

What is the new behavior?

Removed the warning message by removing the flag in the install_site.sh file:

Closes #8728

Other information?

[codecov]

Codecov Report

Merging #8952 (0049bca) into main (907df66) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##               main    #8952   +/-   ##
=========================================
  Coverage     23.24%   23.24%           
  Complexity     7797     7797           
=========================================
  Files           220      220           
  Lines         27271    27271           
  Branches         70       70           
=========================================
  Hits           6340     6340           
  Misses        20863    20863           
  Partials         68       68           

Flag	Coverage Δ
autograder	20.45% <ø> (ø)
js	28.47% <ø> (ø)
migrator	100.00% <ø> (ø)
php	20.19% <ø> (ø)
python_submitty_utils	71.65% <ø> (ø)
submitty_daemon_jobs	91.01% <ø> (ø)

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