vscode设置终端主题，设置终端选中颜色

vscode定义主题色官网：
https://code.visualstudio.com/api/references/theme-color#integrated-terminal-colors

问题：
  终端选中颜色和终端背景颜色一致时，不能显示出光标选中的内容，并且网上搜索了各种主题设置，没有提到终端选中属性的颜色

解决：
  通过查找vscode官方资料，找到terminal.selectionBackground属性，可以通过调整terminal.selectionBackground属性，设置终端选中内容的颜色

完整终端属性：
  terminal.background: The background of the Integrated Terminal's viewport.
  terminal.border: The color of the border that separates split panes within the terminal. This defaults to panel.border.
  terminal.foreground: The default foreground color of the Integrated Terminal.
  terminal.ansiBlack: 'Black' ANSI color in the terminal.
  terminal.ansiBlue: 'Blue' ANSI color in the terminal.
  terminal.ansiBrightBlack: 'BrightBlack' ANSI color in the terminal.
  terminal.ansiBrightBlue: 'BrightBlue' ANSI color in the terminal.
  terminal.ansiBrightCyan: 'BrightCyan' ANSI color in the terminal.
  terminal.ansiBrightGreen: 'BrightGreen' ANSI color in the terminal.
  terminal.ansiBrightMagenta: 'BrightMagenta' ANSI color in the terminal.
  terminal.ansiBrightRed: 'BrightRed' ANSI color in the terminal.
  terminal.ansiBrightWhite: 'BrightWhite' ANSI color in the terminal.
  terminal.ansiBrightYellow: 'BrightYellow' ANSI color in the terminal.
  terminal.ansiCyan: 'Cyan' ANSI color in the terminal.
  terminal.ansiGreen: 'Green' ANSI color in the terminal.
  terminal.ansiMagenta: 'Magenta' ANSI color in the terminal.
  terminal.ansiRed: 'Red' ANSI color in the terminal.
  terminal.ansiWhite: 'White' ANSI color in the terminal.
  terminal.ansiYellow: 'Yellow' ANSI color in the terminal.
  terminal.selectionBackground: The selection background color of the terminal.