Remove TravisCI mentions from build scripts

Travis CI is not used anymore, remove its mentions from the build scripts.

.github/workflows/ci.yml

@@ -8,7 +8,6 @@ on:
     paths-ignore:
       - '.github/workflows/ci_msw_cross.yml'
       - 'build/tools/appveyor*.bat'
-      - 'build/tools/travis-ci.sh'
       - 'distrib/**'
       - 'docs/**'
       - 'interface/**'
@@ -25,7 +24,6 @@ on:
     paths-ignore:
       - '.github/workflows/ci_msw_cross.yml'
       - 'build/tools/appveyor*.bat'
-      - 'build/tools/travis-ci.sh'
       - 'distrib/**'
       - 'docs/**'
       - 'interface/**'

.github/workflows/ci_msw_cross.yml

@@ -8,7 +8,6 @@ on:
     paths-ignore:
       - '.github/workflows/ci.yml'
       - 'build/tools/appveyor*.bat'
-      - 'build/tools/travis-ci.sh'
       - 'distrib/**'
       - 'docs/**'
       - 'interface/**'
@@ -27,7 +26,6 @@ on:
     paths-ignore:
       - '.github/workflows/ci.yml'
       - 'build/tools/appveyor*.bat'
-      - 'build/tools/travis-ci.sh'
       - 'distrib/**'
       - 'docs/**'
       - 'interface/**'