Update cheatsheets

eval

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+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# eval
+
+> Execute arguments as a single command in the current shell and return its result.
+> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#eval>.
+
+- Call `echo` with the "foo" argument:
+
+`eval "{{echo foo}}"`
+
+- Set a variable in the current shell:
+
+`eval "{{foo=bar}}"`