chore: update dependencies and devDependencies:

 @babel/cli                                 ^7.11.5  →  ^7.12.7
 @babel/core                                ^7.11.5  →  ^7.12.7
 @babel/plugin-proposal-object-rest-spread  ^7.11.0  →  ^7.12.1
 @babel/preset-env                          ^7.11.5  →  ^7.12.7
 @popperjs/core                              ^2.4.4  →   ^2.5.4
 @rollup/plugin-babel                        ^5.2.0  →   ^5.2.1
 @rollup/plugin-commonjs                    ^15.0.0  →  ^16.0.0
 @rollup/plugin-node-resolve                 ^9.0.0  →  ^10.0.0
 @rollup/plugin-replace                      ^2.3.3  →   ^2.3.4
 autoprefixer                                ^9.8.6  →  ^10.0.2
 copyfiles                                   ^2.3.0  →   ^2.4.0
 eslint                                      ^7.8.1  →  ^7.14.0
 eslint-config-xo                           ^0.32.1  →  ^0.33.1
 eslint-plugin-import                       ^2.22.0  →  ^2.22.1
 eslint-plugin-unicorn                      ^21.0.0  →  ^23.0.0
 find-unused-sass-variables                  ^2.0.0  →   ^3.0.0
 karma                                       ^5.2.0  →   ^5.2.3
 karma-firefox-launcher                      ^1.3.0  →   ^2.1.0
 node-sass                                  ^4.14.1  →   ^5.0.0
 nodemon                                     ^2.0.4  →   ^2.0.6
 postcss-cli                                 ^7.1.2  →   ^8.3.0
 postcss-combine-duplicated-selectors        ^9.0.0  →  ^10.0.2
 rollup                                     ^2.26.9  →  ^2.33.3
 shx                                         ^0.3.2  →   ^0.3.3
 stylelint                                   13.6.1  →   13.8.0
 terser                                      ^5.2.1  →   ^5.5.0

Author: mrholek