[clang-repl] Remove redundant shared flag while running clang-repl in browser (llvm#118107)

While running clang-repl in the browser, we would be interested in this
cc1 command

`
"" -cc1 -triple wasm32-unknown-emscripten -emit-obj -disable-free
-clear-ast-before-backend -disable-llvm-verifier -discard-value-names
-main-file-name "<<< inputs >>>" -mrelocation-model static
-mframe-pointer=none -ffp-contract=on -fno-rounding-math
-mconstructor-aliases -target-cpu generic -debugger-tuning=gdb
-fdebug-compilation-dir=/ -v -fcoverage-compilation-dir=/ -resource-dir
/lib/clang/19 -internal-isystem /include/wasm32-emscripten/c++/v1
-internal-isystem /include/c++/v1 -internal-isystem
/lib/clang/19/include -internal-isystem /include/wasm32-emscripten
-internal-isystem /include -std=c++17 -fdeprecated-macro -ferror-limit
19 -fvisibility=default -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf
-fcxx-exceptions -fexceptions -fincremental-extensions -o "<<< inputs
>>>.o" -x c++ "<<< inputs >>>"
`

As can be seen `shared` is anyway overwritten by `static` which is also
what would be provided by default. Hence we can get rid of the shared
flag here.

Author: anutosh491

clang/lib/Interpreter/Interpreter.cpp

@@ -200,7 +200,6 @@ IncrementalCompilerBuilder::CreateCpp() {
 #ifdef __EMSCRIPTEN__
   Argv.push_back("-target");
   Argv.push_back("wasm32-unknown-emscripten");
-  Argv.push_back("-shared");
   Argv.push_back("-fvisibility=default");
 #endif
   Argv.insert(Argv.end(), UserArgs.begin(), UserArgs.end());