Fixes #387: Fix for gradle distribution url and spotless plugin

[kbhardwaj123]

Fixes #387

Changed the gradle distribution version and the spotless gradle plugin which were resulting in travis build faliure

[ujjwalagrawal17]

@kbhardwaj123 Travis build is still failing.

[kbhardwaj123]

@ujjwalagrawal17 Yes i checked it as well
Before this PR the logs were:

* What went wrong:
An exception occurred applying plugin request [id: 'com.diffplug.gradle.spotless', version: '5.1.1']
> Failed to apply plugin [id 'com.diffplug.gradle.spotless']
   > We have moved from 'com.diffplug.gradle.spotless'
                     to 'com.diffplug.spotless'
     To migrate:
     - Test your build with: id 'com.diffplug.gradle.spotless' version '4.5.1'
     - Fix any deprecation warnings (shouldn't be many / any)
     - Now you can use:      id 'com.diffplug.spotless' version '5.0.0'
     
     That's all you really need to know, but as always, there are more details in the changelog:
     https://github.com/diffplug/spotless/blob/main/plugin-gradle/CHANGES.md
     
     While you're at it, you might want to search for "target '**/".  We used
     to  recommend that in our README, but it's a lot slower than something
     more specific like "target 'src/**".  Also, if you haven't tried them yet,
     take a look at our IDE integration and 'ratchetFrom'.  We've found them
     to be useful, hope you do too.
     
     If you like the idea behind 'ratchetFrom', you should checkout spotless-changelog
     https://github.com/diffplug/spotless-changelog

Here the issue was with the spotless plugin and then with the gradle distribution url.
After the PR the logs are failing due to lint check

> Task :app:ktlintMainSourceSetCheck FAILED
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:ktlintMainSourceSetCheck'.
> Process 'command '/usr/lib/jvm/java-8-oracle/bin/java'' finished with non-zero exit value 1

The gradle part has been fixed so i will post a new PR for this app:ktlintMainSourceSetCheck issue.

[ujjwalagrawal17]

Got it. Thanks for the PR !