For me adding the float
package and then \floatplacement{figure}{H}
in YAML solved the issue like :
---
title: "test"
date: "`r Sys.Date()`"
output:
pdf_document :
keep_tex: true
number_sections: true
header-includes:
\usepackage{booktabs}
\usepackage{longtable}
\usepackage{array}
\usepackage{multirow}
\usepackage[table]{xcolor}
\usepackage{wrapfig}
\usepackage{float}
\floatplacement{figure}{H}
---