Fix the issues reported by PHP_CodeSniffer

Problem/Motivation

FILE: modules\stepbystep\src\SequenceManager.php
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FOUND 1 ERROR AFFECTING 1 LINE
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57 | ERROR | [x] list(...) is forbidden, use [...] instead.
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PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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FILE: modules\stepbystep\tests\README.txt
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FOUND 0 ERRORS AND 2 WARNINGS AFFECTING 2 LINES
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3 | WARNING | Line exceeds 80 characters; contains 83 characters
11 | WARNING | Line exceeds 80 characters; contains 137 characters
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FILE: modules\stepbystep\tests\src\Functional\StepByStepTest.php
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FOUND 4 ERRORS AFFECTING 2 LINES
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48 | ERROR | The array declaration extends to column 127 (the limit is 120). The array content should be split up over multiple lines
48 | ERROR | The array declaration extends to column 126 (the limit is 120). The array content should be split up over multiple lines
52 | ERROR | The array declaration extends to column 127 (the limit is 120). The array content should be split up over multiple lines
52 | ERROR | The array declaration extends to column 126 (the limit is 120). The array content should be split up over multiple lines
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Steps to reproduce

Run phpcs command to get the drupal coding standard issues.

Proposed resolution

Many of the issues can be fixed by running the phpcbf command. For the remaining ones, we will need to manually address and then commit these changes before pushing them.