Relax Markdown check rules in Linter

[razvand]

The linter Markdown check for PR #151 shows issues that that should be ignored:

/github/workspace/content/en/blog/2022-10-25-unikraft-munich-2022.md:8:23 MD026/no-trailing-punctuation Trailing punctuation in heading [Punctuation: '!']
/github/workspace/content/en/blog/2022-10-25-unikraft-munich-2022.md:18:47 MD026/no-trailing-punctuation Trailing punctuation in heading [Punctuation: '!']
/github/workspace/content/en/blog/2022-10-25-unikraft-munich-2022.md:42:55 MD101/backtick-keywords Keywords must be fenced and must be in appropriate case. [Expected `.png`. Actual .png.]

The have to be corrected in the Markdown rules for super-linter.