improve Git Bash integration on Windows (microsoft#151105) (microsoft#165428)

Bash sessions should be started as interactive (`-i`) sessions to enable history
commands by default.
This is the same setup used by the official Git for Windows JSON fragment
extension for Windows Terminal.

This does not fix the issue at this time, however, because bash signal handling
on Windows for quit/close/kill signals does not work as expected.

Author: Okeanos

src/vs/platform/terminal/node/terminalProfiles.ts

@@ -208,7 +208,7 @@ async function initializeWindowsProfiles(testPwshSourcePaths?: string[]): Promis
 			`${process.env['LocalAppData']}\\Programs\\Git\\bin\\bash.exe`,
 			`${process.env['UserProfile']}\\scoop\\apps\\git-with-openssh\\current\\bin\\bash.exe`,
 		],
-		args: ['--login']
+		args: ['--login', '-i']
 	});
 	profileSources.set('PowerShell', {
 		profileName: 'PowerShell',