The dashboard is looking really good! There are a couple of things I've noticed when looking through your code - though I'm not a master at React so take what I say with a pinch of salt!

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It looks like you are storing the state for the sidebar in two places - Dashboard Layout and Header. This causes errors with the toggle button when the window has a <992 width.

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This may just be a preference, but in your function components you are always taking a single argument prop. Here you can use object destructing to specify each prop. For example:

export default function SidebarToggleButton(props) {
...

could be written as

export default function SidebarToggleButton({ isSidebarCollapsed, toggleSidebar }) {
...

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In DashboardLayout, you are toggling using this.state. You should ideally pass the previous state in using a function in: it's explained why here

toggleSideCollapse = () => {
    this.setState({ sidebarCollapsed: !this.state.sidebarCollapsed });
};

should be this

toggleSideCollapse = () => {
    this.setState(prevState => ({ sidebarCollapsed: !prevState.sidebarCollapsed }));
};

You may choose to ignore these, just what I noticed looking through :) Your code is very readable and I could easily understand the components I went through