corrected errors in documentation

Author: aman-godara

doc/specs/stdlib_stringlist_type.md

@@ -421,7 +421,7 @@ program demo_equality_operator
   res = ( stringlist == ["#4", "#3", "#2", "#1"] )
     ! res <-- .true.
 
-  print *, stringlist == ["#4", "#3", "#1"]
+  print'(l0)', stringlist == ["#4", "#3", "#1"]
     ! .false.
 
 end program demo_equality_operator
@@ -491,7 +491,7 @@ program demo_inequality_operator
   res = ( stringlist /= ["#111", "#222", "#333", "#444"] )
     ! res <-- .true.
 
-  print *, stringlist /= ["#4", "#3", "#1"]
+  print'(l0)', stringlist /= ["#4", "#3", "#1"]
     ! .true.
 
 end program demo_inequality_operator

doc/specs/stdlib_strings.md

@@ -146,8 +146,8 @@ The result is of scalar logical type.
 program demo
   use stdlib_strings, only : starts_with
   implicit none
-  print'(a)', starts_with("pattern", "pat")  ! T
-  print'(a)', starts_with("pattern", "ern")  ! F
+  print'(l0)', starts_with("pattern", "pat")  ! T
+  print'(l0)', starts_with("pattern", "ern")  ! F
 end program demo
 ```
 
@@ -188,8 +188,8 @@ The result is of scalar logical type.
 program demo
   use stdlib_strings, only : ends_with
   implicit none
-  print'(a)', ends_with("pattern", "ern")  ! T
-  print'(a)', ends_with("pattern", "pat")  ! F
+  print'(l0)', ends_with("pattern", "ern")  ! T
+  print'(l0)', ends_with("pattern", "pat")  ! F
 end program demo
 ```