Use relative links for rules.neon

The changes to default parameters are different in different branches, so we want to link to the current branch's version of `rules.neon`.

Author: simon-tma

README.md

@@ -84,7 +84,7 @@ parameters:
 		illegalConstructorMethodCall: false
 ```
 
-Aside from introducing new custom rules, phpstan-strict-rules also [change the default values of some configuration parameters](https://github.com/phpstan/phpstan-strict-rules/blob/1.6.x/rules.neon#L1) that are present in PHPStan itself. These parameters are [documented on phpstan.org](https://phpstan.org/config-reference#stricter-analysis).
+Aside from introducing new custom rules, phpstan-strict-rules also [change the default values of some configuration parameters](./rules.neon#L1) that are present in PHPStan itself. These parameters are [documented on phpstan.org](https://phpstan.org/config-reference#stricter-analysis).
 
 ## Enabling rules one-by-one
 
@@ -107,4 +107,4 @@ parameters:
 		booleansInConditions: true
 ```
 
-Even with `strictRules.allRules` set to `false`, part of this package is still in effect. That's because phpstan-strict-rules also [change the default values of some configuration parameters](https://github.com/phpstan/phpstan-strict-rules/blob/1.6.x/rules.neon#L1) that are present in PHPStan itself. These parameters are [documented on phpstan.org](https://phpstan.org/config-reference#stricter-analysis).
+Even with `strictRules.allRules` set to `false`, part of this package is still in effect. That's because phpstan-strict-rules also [change the default values of some configuration parameters](./rules.neon#L1) that are present in PHPStan itself. These parameters are [documented on phpstan.org](https://phpstan.org/config-reference#stricter-analysis).