Fix regex pattern to find spaces in placeholders of tms url

[Sujanadh]

Updates:

• refactored the regex pattern to search any spaces within placeholders in the tms url.
• only checks for them if they are present in url.
• pattern is r".*/\{[zxy]\}/\{[zxy]\}/\{[zxy]\}(?:/|/?)" which ensures placeholders without spaces for all possible combination of them, such as {z}{x}{y}, {x}{y}{z} etc.