feat(right): add subject, test and solution for the exercise

sh/tests/right_test.sh

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+#!/usr/bin/env bash
+
+# Unofficial Bash Strict Mode
+set -euo pipefail
+IFS='
+'
+
+FILENAME="student/right.sh"
+script_dirS=$(cd -P "$(dirname "$BASH_SOURCE")" &>/dev/null && pwd)
+
+challenge() {
+    submitted=$(cd "$1" && bash "$script_dirS"/$FILENAME)
+    expected=$(cd "$1" && bash "$script_dirS"/solutions/right.sh)
+    diff <(echo "$submitted") <(echo "$expected")
+    diff $1"/filtered_files_sol.txt" $1"/filtered_files.txt"
+}
+
+challenge right

sh/tests/solutions/right.sh

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+ls | grep -v "\.txt" >filtered_files_sol.txt

subjects/devops/right/README.md

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+## right
+
+### Instructions
+
+Create a file `right.sh` that will get the output of a file and parse it, and then write it to a file with a specific format using a single command.
+
+Get the output of the `ls` command, parse it with the `grep` command to filter for files without a `.txt` extension, and write the output to a file called `filtered_files.txt`, check the example bellow:
+
+### Usage
+
+```console
+$ ls -l
+sample1.txt sample2 sample3.txt sample4
+$ ./right.sh
+$ cat filtered_files.txt
+sample2
+sample4
+$
+```
+
+### Hints
+
+command1 | command2 > output_file
+
+Here, command1 is the command that generates the output you want to parse, and command2 is the command that parses the output. The output of command2 will be redirected to the file output_file using the > operator.
+
+> You have to use Man or Google to know more about commands flags, in order to solve this exercise!
+> Google and Man will be your friends!