update example in docs

[EthBerryAdmin]

according to these findings

https://github.com/ggozad/oterm/issues/188#issuecomment-2726734938 https://github.com/ggozad/oterm/issues/171#issuecomment-2645731772

people are misusing your example with git moreover docker could be missing from the system

I propose to replace git mcp with simpler one

{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-filesystem",
        "~"
      ]
    }
  }
}