refactor: use constants/float32/nan in stats/strided/snanmeanpn

[manit2004]

type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes. report:

• task: lint_filenames status: passed
• task: lint_editorconfig status: passed
• task: lint_markdown status: passed
• task: lint_package_json status: na
• task: lint_repl_help status: na
• task: lint_javascript_src status: na
• task: lint_javascript_cli status: na
• task: lint_javascript_examples status: na
• task: lint_javascript_tests status: na
• task: lint_javascript_benchmarks status: na
• task: lint_python status: na
• task: lint_r status: na
• task: lint_c_src status: missing_dependencies
• task: lint_c_examples status: missing_dependencies
• task: lint_c_benchmarks status: missing_dependencies
• task: lint_c_tests_fixtures status: na
• task: lint_shell status: na
• task: lint_typescript_declarations status: passed
• task: lint_typescript_tests status: na
• task: lint_license_headers status: passed ---

Resolves #11743 .

Description

What is the purpose of this pull request?

This pull request:

• Replace inline 0.0f/0.0f Float32 NaN generation with STDLIB_CONSTANT_FLOAT32_NAN macro from constants/float32/nan

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Coverage Report

Package	Statements	Branches	Functions	Lines
stats/strided/snanmeanpn	$\color{green}404/404$ $\color{green}+0.00%$	$\color{green}26/26$ $\color{green}+0.00%$	$\color{green}4/4$ $\color{green}+0.00%$	$\color{green}404/404$ $\color{green}+0.00%$

The above coverage report was generated for the changes in this PR.

[manit2004]

@anandkaranubc Please take a look.

[anandkaranubc]

Why double?

[anandkaranubc]

Same comment..