graphviz: add page

[UsmanAhmadSaeed]

graphviz: add page

• The page(s) are in the correct platform directories: common, linux, osx, windows, sunos, android, etc.
• The page description(s) have links to documentation or a homepage.
• The page(s) follow the content guidelines.
• The page(s) follow the style guide.
• The PR contains at most 5 new pages.
• The PR title conforms to the recommended templates.
• Version of the command being documented (if known): 14.0.1
• References Hacktoberfest issues to get started with #18405 (Hacktoberfest beginner-friendly page requests)

[CLAassistant]

All committers have signed the CLA.

[tldr-bot]

The build for this PR failed with the following error(s) at commit
fa0ba1e9b4154a80fc43064f2d2270fadd1bc6c4:

pages/common/graphviz.md:6: TLDR014 Page should contain no trailing whitespace
pages/common/graphviz.md:7: TLDR007 Example descriptions should be surrounded by empty lines
pages/common/graphviz.md:9: TLDR014 Page should contain no trailing whitespace
pages/common/graphviz.md:10: TLDR007 Example descriptions should be surrounded by empty lines
pages/common/graphviz.md:12: TLDR014 Page should contain no trailing whitespace
pages/common/graphviz.md:13: TLDR007 Example descriptions should be surrounded by empty lines
pages/common/graphviz.md:15: TLDR014 Page should contain no trailing whitespace
pages/common/graphviz.md:16: TLDR007 Example descriptions should be surrounded by empty lines
pages/common/graphviz.md:18: TLDR014 Page should contain no trailing whitespace
pages/common/graphviz.md:19: TLDR007 Example descriptions should be surrounded by empty lines
pages/common/graphviz.md:21: TLDR014 Page should contain no trailing whitespace
pages/common/graphviz.md:22: TLDR007 Example descriptions should be surrounded by empty lines
pages/common/graphviz.md:24: TLDR014 Page should contain no trailing whitespace
pages/common/graphviz.md:25: TLDR007 Example descriptions should be surrounded by empty lines
pages/common/graphviz.md:27: TLDR014 Page should contain no trailing whitespace
pages/common/graphviz.md:28: TLDR007 Example descriptions should be surrounded by empty lines

Please fix the error(s) and push again.

[Managor]

Graphviz is not a terminal program and dot.md already exists