Improve handling for unavailable UI5 APIs

[marianfoo]

Some UI5 APIs are deprecated and removed and replaced by other UI5 APIs. There is logic to check if library is availabe.

The sap.ui.require(["..."], function) does not check if the library is already loaded.
Change it to execute sap.ui.require("...") first to check if library already loaded, if not, execute sap.ui.require(["..."], function).

ui5-cc-spreadsheetimporter/packages/ui5-cc-spreadsheetimporter/src/controller/Util.ts

Lines 184 to 196 in 7500dde

	static async loadUI5RessourceAsync(libraryName: string): Promise<any> {
	return new Promise(function (resolve, reject) {
	sap.ui.require(
	[libraryName],
	function (Library: unknown) {
	resolve(Library);
	},
	function (err: any) {
	reject(err);
	}
	);
	});
	}