ci: GCC version requirement is >=5.0

.drone.star

@@ -14,7 +14,7 @@ def main(ctx):
     return generate(
         # Compilers
         [
-            'gcc >=4.8',
+            'gcc >=5.0',
             'clang >=3.8',
             'msvc >=14.1',
             'arm64-gcc latest',

.github/workflows/ci.yml

@@ -57,7 +57,7 @@ jobs:
         id: cpp-matrix
         with:
           compilers: |
-            gcc >=4.8
+            gcc >=5.0
             clang >=3.8
             msvc >=14.20
             apple-clang *

doc/library-detail.adoc

@@ -138,9 +138,9 @@ work without exceptions if desired.
 
 Boost.URL is tested with the following compilers:
 
-* clang: 3.8, 4, 5, 6, 7, 8, 9, 10, 11, 12
-* gcc: 4.8, 4.9, 5, 6, 7, 8, 9, 10, 11
-* msvc: 14.0, 14.1, 14.2, 14.3
+* clang: >=3.8
+* gcc: >=5
+* msvc: >=14
 
 and these architectures: x86, x64, ARM64, S390x