feat: add php solution to lc problem: No.0026 (doocs#973)

Author: Qiu-IT

solution/0000-0099/0026.Remove Duplicates from Sorted Array/README.md

@@ -198,6 +198,27 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param Integer[] $nums
+     * @return Integer
+     */
+    function removeDuplicates(&$nums) {
+        $fast = $slow = 0;
+        while ($fast < count($nums)) {
+            if ($nums[$fast] != $nums[$slow]) {
+                $nums[++$slow] = $nums[$fast];
+            }
+            $fast++;
+        }
+        return $slow + 1;
+    }
+}
+```
+
 ### **...**
 
 ```

solution/0000-0099/0026.Remove Duplicates from Sorted Array/README_EN.md

@@ -185,6 +185,27 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param Integer[] $nums
+     * @return Integer
+     */
+    function removeDuplicates(&$nums) {
+        $fast = $slow = 0;
+        while ($fast < count($nums)) {
+            if ($nums[$fast] != $nums[$slow]) {
+                $nums[++$slow] = $nums[$fast];
+            }
+            $fast++;
+        }
+        return $slow + 1;
+    }
+}
+```
+
 ### **...**
 
 ```

solution/0000-0099/0026.Remove Duplicates from Sorted Array/Solution.php

@@ -0,0 +1,16 @@
+class Solution {
+    /**
+     * @param Integer[] $nums
+     * @return Integer
+     */
+    function removeDuplicates(&$nums) {
+        $fast = $slow = 0;
+        while ($fast < count($nums)) {
+            if ($nums[$fast] != $nums[$slow]) {
+                $nums[++$slow] = $nums[$fast];
+            }
+            $fast++;
+        }
+        return $slow + 1;
+    }
+}