Activate URL Handler with DocumentDB connection details

[tnaum-ms]

vscode://ms-azuretools.vscode-documentdb?connectionString=<connection string, but encoded, twice!>

Otherwise mongodb+srv will turn to mongodb srv

vscode://ms-azuretools.vscode-documentdb?connectionString=mongodb%252Bsrv%253A%252F%252Ftomek%2540tnaumowicz-cosvcore2.global.mongocluster.cosmos.azure.com%252F%253Ftls%253Dtrue%2526authMechanism%253DSCRAM-SHA-256%2526retrywrites%253Dfalse%2526maxIdleTimeMS%253D120000

vscode://ms-azuretools.vscode-documentdb?connectionString=mongodb%252Bsrv%253A%252F%252Ftomek%2540tnaumowicz-cosvcore2.global.mongocluster.cosmos.azure.com%252F%253Ftls%253Dtrue%2526authMechanism%253DSCRAM-SHA-256%2526retrywrites%253Dfalse%2526maxIdleTimeMS%253D120000&database=demoDatabase

vscode://ms-azuretools.vscode-documentdb?connectionString=mongodb%252Bsrv%253A%252F%252Ftomek%2540tnaumowicz-cosvcore2.global.mongocluster.cosmos.azure.com%252F%253Ftls%253Dtrue%2526authMechanism%253DSCRAM-SHA-256%2526retrywrites%253Dfalse%2526maxIdleTimeMS%253D120000&database=demoDatabase&collection=demo